chore: add examples of how to configure

.gitignore

@@ -6,7 +6,7 @@ deps
 *.o
 *.beam
 *.plt
-*.example
+#*.example
 erl_crash.dump
 ebin
 !ebin/.placeholder

delayed.conf.example

@@ -0,0 +1,15 @@
+##--------------------------------------------------------------------
+## Delayed publish
+##
+## Configuring the delayed publish feature
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+delayed {
+    enable = true ## false for disabled
+
+    ## Maximum number of delayed messages
+    ## Default: 0 (0 is no limit)
+    max_delayed_messages = 0
+}

examples/README.md

@@ -0,0 +1,16 @@
+# Examples
+
+Here are examples of how to configure features In EMQX,  most of them can be used directly by copy-paste content into the `emqx.conf` file, others may need to be slightly modified to use, for example, you should change the listener port or HTTP URL to what you actually used.
+
+Although we have tried to show every configurable field in the example,
+you do not need to care about each one, since most of them already have default values and can be omitted in the configuration file.
+
+If you are confused about some fields, please refer to our documents, here are just some simple configuration examples with necessary descriptions.
+
+
+## Documentation
+
+The EMQX documentation is available at [www.emqx.io/docs/en/latest/](https://www.emqx.io/docs/en/latest/).
+
+The EMQX Enterprise documentation is available at [docs.emqx.com/en/](https://docs.emqx.com/en/).
+

examples/alarm.conf.example

@@ -0,0 +1,22 @@
+##--------------------------------------------------------------------
+## Alarm
+##
+## Configuring how to handle the alarms generated from sysmon.*.conf.example
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+alarm {
+    ## The actions triggered when the alarm is activated
+    ## Type: Array of the below enum
+    ##   - log :: write the alarm to log
+    ##   - publish :: publish the alarm as an MQTT message to the system topics
+    actions = [log]
+
+    ## Maximum total number of deactivated alarms to keep as history
+    ## Type: Range from 1 to 3000
+    size_limit = 1000
+
+    ## Retention time of deactivated alarms
+    validity_period = 24h
+}

examples/auto_subscribe.conf.example

@@ -0,0 +1,30 @@
+##--------------------------------------------------------------------
+## Auto Subscribe
+##
+## Subscribe the Topics automatically when client connected
+##--------------------------------------------------------------------
+
+auto_subscribe.topics = [
+    {
+        ## Topic name, placeholders are supported
+        ## For example: client/${clientid}/username/${username}/host/${host}/port/${port}
+        topic = "/auto/${clientid}",
+
+        ## QoS
+        qos = 0,
+
+        ## Retain Handling
+        ## Value: 0 | 1 | 2
+        rh = 0,
+
+        ## Retain As Publish
+        ## Value: 0 | 1
+        rap = 0,
+
+        ## No Local
+        ## Value: 0 | 1
+        nl = 0
+    },
+    {topic = "/foo/${username}/#", qos = 1},
+    {topic = "/boo/${ip}/+"}
+]

examples/broker.conf.example

@@ -0,0 +1,30 @@
+##--------------------------------------------------------------------
+## Broker
+##
+## Message broker options
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: If you and finding how to configure EMQX itself, have a look at the node.conf.example
+
+broker {
+    ## Session locking strategy in a cluster
+    ## Type:
+    ##   - local :: only lock the session on the current node
+    ##   - leader :: select only one remote node to lock the session
+    ##   - quorum :: select some nodes to lock the session
+    ##   - all :: lock the session on all the nodes in the cluster
+    session_locking_strategy = quorum
+
+    ## Dispatch strategy for shared subscription
+    ## Type:
+    ##   - random :: dispatch the message to a random selected subscriber
+    ##   - round_robin :: select the subscribers in a round-robin manner
+    ##   - round_robin_per_group :: select the subscribers in round-robin fashion within each shared subscriber group
+    ##   - local :: select random local subscriber otherwise select random cluster-wide
+    ##   - sticky :: always use the last selected subscriber to dispatch, until the subscriber disconnects.
+    ##   - hash_clientid :: select the subscribers by hashing the `clientIds`
+    ##   - hash_topic :: select the subscribers by hashing the source topic"""
+    shared_subscription_strategy = round_robin
+ }

examples/cluster-with-dns.conf.example

@@ -0,0 +1,33 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery via DNS SRV records mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = dns
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    dns {
+      ## The domain name from which to discover peer EMQX nodes' IP addresses
+      name = localhost
+
+      ## DNS record type
+      ## Type: enum: a | srv
+      record_type = a
+     }
+ }

examples/cluster-with-etcd-ssl.conf.example

@@ -0,0 +1,84 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery using 'etcd' service mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = etcd
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    etcd {
+      ## List of endpoint URLs of the etcd cluster
+      server = "http://ur1,http://ur2"
+
+      ## Key prefix used for EMQX service discovery
+      prefix = emqxcl
+
+      ## Expiration time of the etcd key associated with the node.
+      node_ttl = 1m
+
+      ssl_options {
+          ## Trusted PEM format CA certificates bundle file
+          cacertfile = "data/certs/cacert.pem"
+
+          ## PEM format certificates chain file
+          certfile = "data/certs/cert.pem"
+
+          ## PEM format private key file
+          keyfile = "data/certs/key.pem"
+
+          ## Enable or disable peer verification
+          verify = verify_none ## use verify_peer to enable
+
+          ## if `verify' is ebabled, whit true, the connection fails if the client does not have a certificate to send
+          fail_if_no_peer_cert = false
+
+          ## Enable TLS session reuse
+          reuse_sessions = true
+
+          ## Maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path
+          depth = 10
+
+          ## Which versions are to be supported
+          versions = [tlsv1.3, tlsv1.2]
+
+          ## TLS cipher suite names
+          ## Note: By default, all available suites are supported, you do not need to set this
+          ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+
+          ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
+          secure_renegotiate = true
+
+          ## Log level for SSL communication
+          ## Type: emergency | alert | critical | error | warning | notice | info | debug | none | all
+          log_level = notice
+
+          ## Hibernate the SSL process after idling for amount of time reducing its memory footprint
+          hibernate_after = 5s
+
+          ## Forces the cipher to be set based on the server-specified order instead of the client-specified order
+           honor_cipher_order = true
+
+          ##  Setting this to false to disable client-initiated renegotiation
+           client_renegotiation = true
+
+          ## Maximum time duration allowed for the handshake to complete
+           handshake_timeout = 15s
+      }
+    }
+}

examples/cluster-with-etcd.conf.example

@@ -0,0 +1,36 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery using 'etcd' service mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = etcd
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    etcd {
+      ## List of endpoint URLs of the etcd cluster
+      ## Type: Comma Separated String
+      server = "http://ur1,http://ur2"
+
+      ## Key prefix used for EMQX service discovery
+      prefix = emqxcl
+
+      ## Expiration time of the etcd key associated with the node
+      node_ttl = 1m
+    }
+}

examples/cluster-with-k8s.conf.example

@@ -0,0 +1,42 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery via Kubernetes API server mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = k8s
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    k8s {
+      ## Kubernetes API endpoint URL
+      apiserver = "http://10.110.111.204:8080"
+
+      ## EMQX broker service name
+      service_name = emqx
+
+      ## Address type used for connecting to the discovered nodes
+      ## Type: ip | dns | hostname
+      address_type = ip
+
+      ## Kubernetes namespace
+      namespace = default
+
+      ## Node name suffix
+      suffix = "pod.local"
+    }
+}

examples/cluster-with-manual.conf.example

@@ -0,0 +1,24 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery via manual join mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = manual
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+ }

examples/cluster-with-static.conf.example

@@ -0,0 +1,27 @@
+##--------------------------------------------------------------------
+## Cluster in service discovery via static nodes mode
+##
+## Configs to instruct how individual nodes can discover each other
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+cluster {
+    ## Human-friendly name of the EMQX cluster.
+    name = emqxcl
+
+    ## Service discovery method for the cluster nodes
+    discovery_strategy = static
+
+    ## List of core nodes that the replicant will connect to
+    core_nodes = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+
+    ## Remove disconnected nodes from the cluster after this interval
+    autoclean = 5m
+
+    ## If true, the node will try to heal network partitions automatically
+    autoheal = true
+
+    ## List EMQX node names in the static cluster
+    static.seeds = ['emqx1@192.168.0.1', 'emqx2@192.168.0.2']
+ }

examples/conn_congestion.conf.example

@@ -0,0 +1,15 @@
+##--------------------------------------------------------------------
+## Connection Congestion
+##
+## Generating alarm when MQTT connection congested
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+conn_congestion {
+    ## Enable or disable connection congestion alarm
+    enable_alarm = true
+
+    ## Minimal time before clearing the alarm
+    min_alarm_sustain_duration = 1m
+}

examples/dashboard-with-http.conf.example

@@ -0,0 +1,44 @@
+##--------------------------------------------------------------------
+## Dashboard with HTTP Listener
+##
+## Configuration for EMQX dashboard
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+dashboard {
+    ## JWT token expiration time
+    token_expired_time = 60m
+
+    ## Support Cross-Origin Resource Sharing (CORS)
+    cors = false
+
+    listeners.http {
+        ## Whether to enable the listener
+        enable = true
+
+        ## Port or Address to listen on
+        bind = "0.0.0.0:18083" ## or just a port number, e.g. 18083
+
+        ## Socket acceptor pool size for TCP protocols
+        num_acceptors = 8
+
+        ## Maximum number of simultaneous connections
+        max_connections = 512
+
+        ## Defines the maximum length that the queue of pending connections can grow to
+        backlog = 1024
+
+        ## Send timeout for the socket
+        send_timeout = 10s
+
+        ## Enable IPv6 support, default is false, which means IPv4 only
+        inet6 = false
+
+        ## Disable IPv4-to-IPv6 mapping for the listener
+        ipv6_v6only = false
+
+        ## Enable support for `HAProxy` header
+        proxy_header = false
+    }
+}

examples/dashboard-with-https.conf.example

@@ -0,0 +1,91 @@
+##--------------------------------------------------------------------
+## Dashboard with HTTPS Listener
+##
+## Configuration for EMQX dashboard
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+dashboard {
+    ## JWT token expiration time
+    token_expired_time = 60m
+
+    ## Support Cross-Origin Resource Sharing (CORS)
+    cors = false
+
+    listeners.https {
+        ## Whether to enable the listener
+        enable = true
+
+        ## Port or Address to listen on
+        bind = "0.0.0.0:18084" ## or just a port number, e.g. 18084
+
+        ## Socket acceptor pool size for TCP protocols
+        num_acceptors = 8
+
+        ## Maximum number of simultaneous connections
+        max_connections = 512
+
+        ## Defines the maximum length that the queue of pending connections can grow to
+        backlog = 1024
+
+        ## Send timeout for the socket
+        send_timeout = 10s
+
+        ## Enable IPv6 support, default is false, which means IPv4 only
+        inet6 = false
+
+        ## Disable IPv4-to-IPv6 mapping for the listener
+        ipv6_v6only = false
+
+        ## Enable support for `HAProxy` header
+        proxy_header = false
+
+        ## Trusted PEM format CA certificates bundle file
+        cacertfile = "data/certs/cacert.pem"
+    
+        ## PEM format certificates chain file
+        certfile = "data/certs/cert.pem"
+    
+        ## PEM format private key file
+        keyfile = "data/certs/key.pem"
+    
+        ## Enable or disable peer verification
+        verify = verify_none  ## use verify_peer to enable
+    
+        ## if `verify' is ebabled, whit true, the connection fails if the client does not have a certificate to send
+        fail_if_no_peer_cert = false
+    
+        ## Enable TLS session reuse
+        reuse_sessions = true
+    
+        ## Maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path
+        depth = 10
+    
+        ## Which versions are to be supported
+        versions = [tlsv1.3, tlsv1.2]
+    
+        ## TLS cipher suite names
+        ## Note: By default, all available suites are supported, you do not need to set this
+        ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+    
+        ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
+        secure_renegotiate = true
+    
+        ## Log level for SSL communication
+        ## Type: emergency | alert | critical | error | warning | notice | info | debug | none | all
+        log_level = notice
+    
+        ## Hibernate the SSL process after idling for amount of time reducing its memory footprint
+        hibernate_after = 5s
+    
+        ## Forces the cipher to be set based on the server-specified order instead of the client-specified order
+        honor_cipher_order = true
+    
+        ##  Setting this to false to disable client-initiated renegotiation
+        client_renegotiation = true
+    
+        ## Maximum time duration allowed for the handshake to complete
+        handshake_timeout = 15s
+    }
+}

examples/exhook.conf.example

@@ -0,0 +1,52 @@
+##--------------------------------------------------------------------
+## gRPC Hook Extension
+##
+## Allows users to process EMQX Hooks using other programming languages
+##--------------------------------------------------------------------
+
+exhook.servers = [
+    {
+        ## Name of the exhook server
+        name = "server_1"
+
+        ## Feature switch
+        enable = false
+
+        ## URL of gRPC server
+        url = "http://127.0.0.1:9090"
+
+        ## The timeout of request gRPC server
+        request_timeout = 5s
+
+        ## This value will be returned when the request to the gRPC server fails for any reason
+        ## Type:
+        ## - deny :: stop to execute this hook.
+        ## - ignore :: continue to execute this hook
+        failed_action = deny
+
+        ## Interval of automatically reconnecting the gRPC server when the connection is broken
+        ## Type:
+        ## - false :: Never reconnect
+        ## - Time Duration, e.g.15s, 10m, 1h :: Reconnecting Interval
+        auto_reconnect = 60s
+
+        ## The process pool size for gRPC client
+        pool_size = 8
+
+        ## Connection socket options
+        socket_options {
+            ## Whether periodic transmission on a connected socket when no other data is exchanged
+            keepalive = true
+
+            ## TCP_NODELAY switch
+            nodelay = true
+
+            ## The minimum size of receive buffer to use for the socket
+            recbuf = "64KB"
+
+            ## The minimum size of send buffer to use for the socket
+            sndbuf = "16KB"
+        }
+    },
+    {name = "server_2", url = "http://127.0.0.1:9091"}
+]

examples/file_transfer-with-local-exporter.conf.example

@@ -0,0 +1,50 @@
+##--------------------------------------------------------------------
+## File Transfer
+##
+## Enables the File Transfer over MQTT feature
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: This configuration only works for the EMQX Enterprise version
+
+file_transfer {
+    ## Enable the File Transfer feature
+    enable = true
+
+    ## Storage backend settings
+    storage {
+        ## Local file system backend setting
+        ## Currently, it's the only available storage backend.
+        local {
+            ## Enable the backend
+            enable = true
+
+            ## Segments and temporary files storage settings
+            segments {
+                ## Directory where these files are stored
+                root = "/var/lib/emqx/transfers/segments"
+
+                ## Garbage collection settings
+                gc {
+                    ## How often to run GC
+                    interval = 1h
+
+                    ## Maximum time to keep parts of incomplete transfers for
+                    maximum_segments_ttl = 24h
+                }
+            }
+
+            ## Local filesystem exporter
+            exporter.local {
+
+                ## Enable the backend
+                ## Note: Only one backend may be enabled at a time
+                enable = true
+
+                ## Directory in the local file system where to store transferred files
+                root = "/var/lib/emqx/transfers/exports"
+            }
+        }
+    }
+}

examples/file_transfer-with-s3-exporter.conf.example

@@ -0,0 +1,71 @@
+##--------------------------------------------------------------------
+## File Transfer
+##
+## Enables the File Transfer over MQTT feature
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: This configuration only works for the EMQX Enterprise version
+
+file_transfer {
+    ## Enable the File Transfer feature
+    enable = true
+
+    ## Storage backend settings
+    storage {
+        ## Local file system backend setting
+        ## Currently, it's the only available storage backend.
+        local {
+            ## Enable the backend
+            enable = true
+
+            ## Segments and temporary files storage settings
+            segments {
+                ## Directory where these files are stored
+                root = "/var/lib/emqx/transfers/segments"
+
+                ## Garbage collection settings
+                gc {
+                    ## How often to run GC
+                    interval = 1h
+
+                    ## Maximum time to keep parts of incomplete transfers for
+                    maximum_segments_ttl = 24h
+                }
+            }
+
+            ## S3-compatible object storage exporter
+            exporter.s3 {
+
+                ## Disable the backend
+                ## Note: Only one backend may be enabled at a time.
+                enable = true
+
+                ## Endpoint of S3 API of the object storage service of your choice
+                host = "s3.us-east-1.amazonaws.com"
+                port = 443
+
+                ## Credentials to use to authorize with the S3 API
+                access_key_id = "AKIA27EZDDM9XLINWXFE"
+                secret_access_key = "..."
+
+                ## Which bucket to store transferred files in?
+                bucket = "my-bucket"
+
+                ## TTL of file download URLs exposed through File Transfer API
+                url_expire_time = 1h
+
+                ## Enable the HTTPS
+                transport_options.ssl.enable = true
+
+                ## Timeout for connection attempts
+                connect_timeout = 15s
+
+                ## Attempt to talk through IPv6 first
+                ipv6_probe = true
+            }
+        }
+
+    }
+}

examples/flapping_detect.conf.example

@@ -0,0 +1,21 @@
+##--------------------------------------------------------------------
+## Flapping Detect
+##
+## Ban the client when the times of connections exceed the limit in the time window
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+flapping_detect {
+    ## Feature switch
+    enable = false
+
+    ## Time window for flapping detection
+    window_time = 1m
+
+    ## Maximum number of connects allowed for a MQTT Client in window_time
+    max_count = 15
+
+    ## How long the flapping clientid will be banned
+    ban_time = 5m
+}

examples/force_gc.conf.example

@@ -0,0 +1,18 @@
+##--------------------------------------------------------------------
+## Force garbage collection
+##
+## Force garbage collection in MQTT connection process after they process certain number of messages or bytes of data
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+force_gc {
+    ## set to false to disable this
+    enable = true
+
+    ## GC the process after this many received messages
+    count = 16000
+
+    ## GC the process after specified number of bytes have passed through
+    bytes = 16MB
+}

examples/force_shutdown.conf.example

@@ -0,0 +1,19 @@
+##--------------------------------------------------------------------
+## Force Shutdown
+##
+## Forced closing of the overloaded session
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+force_shutdown {
+    ## false to disable this
+    enable = true
+
+    ## Maximum mailbox size for each Erlang process
+    ## Note: Do not modify this unless you know what this is for
+    max_mailbox_size = 1000
+
+    ## Maximum heap size for each session process
+    max_heap_size = 32MB
+}

examples/license.conf.example

@@ -0,0 +1,19 @@
+##--------------------------------------------------------------------
+## License
+##
+## Defines the EMQX Enterprise license
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: This configuration only works for the EMQX Enterprise version
+
+license {
+    ## License Key
+    key = "MjIwMTExCjAKMTAKRXZhbHVhdGlvbgpjb250YWN0QGVtcXguaW8KZGVmYXVsdAoyMDIzMDEwOQoxODI1CjEwMAo=.MEUCIG62t8W15g05f1cKx3tA3YgJoR0dmyHOPCdbUxBGxgKKAiEAhHKh8dUwhU+OxNEaOn8mgRDtiT3R8RZooqy6dEsOmDI="
+    ## Low watermark limit below which license connection quota usage alarms are deactivated
+    connection_low_watermark = "75%"
+
+    ## High watermark limit above which license connection quota usage alarms are activated
+    connection_high_watermark = "80%"
+}

examples/listeners.quic.conf.example

@@ -0,0 +1,48 @@
+##--------------------------------------------------------------------
+## QUIC Listener
+##
+## Add a QUIC Listener
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: Modifying the 'quicname' to what you need
+listeners.quic.quicname {
+    ## Whether to enable the listener
+    enable = true
+
+    ## Port or Address to listen on
+    bind = 14567 ## or with an IP, e.g. "127.0.0.1:14567"
+
+    ## When publishing or subscribing, prefix all topics with a mountpoint string
+    mountpoint = "${clientid}/msg"
+
+    ## Client authentication
+    ## Type:
+    ##   - true :: enable
+    ##   - false :: disable
+    ##   - quick_deny_anonymous :: denied immediately without if username is not provided
+    enable_authn = true
+
+    ## Socket acceptor pool size for TCP protocols
+    acceptors = 16
+
+    ## Maximum number of simultaneous connections
+    ## Type: infinity | Integer
+    max_connections = infinity
+
+    ## Trusted PEM format CA certificates bundle file
+    cacertfile = "data/certs/cacert.pem"
+
+    ## PEM format certificates chain file
+    certfile = "data/certs/cert.pem"
+
+    ## PEM format private key file
+    keyfile = "data/certs/key.pem"
+
+    ## Enable or disable peer verification
+    verify = verify_none ## to verify_peer to enable
+
+    ## TLS cipher suite names
+    ciphers = ["TLS_AES_256_GCM_SHA384", "TLS_AES_128_GCM_SHA256", "TLS_CHACHA20_POLY1305_SHA256"]
+}

examples/listeners.ssl.conf.example

@@ -0,0 +1,66 @@
+##--------------------------------------------------------------------
+## SSL Listener
+##
+## Add a SSL Listener
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## The SSL listener also supports all the fields listed in listeners.tcp.conf.example
+## only the SSL-specific fields are shown here
+
+## Note: Modifying the 'sslname' to what you need
+listeners.ssl.sslname {
+    ## Whether to enable the listener
+    enable = true
+
+    ## Port or Address to listen on
+    bind = 8883 ## or with an IP e.g. "127.0.0.1:8883"
+
+    ## Trusted PEM format CA certificates bundle file
+    cacertfile = "data/certs/cacert.pem"
+
+    ## PEM format certificates chain file
+    certfile = "data/certs/cert.pem"
+
+    ## PEM format private key file
+    keyfile = "data/certs/key.pem"
+
+    ## Enable or disable peer verification
+    verify = verify_none  ## use verify_peer to enable
+
+    ## if `verify' is ebabled, whit true, the connection fails if the client does not have a certificate to send
+    fail_if_no_peer_cert = false
+
+    ## Enable TLS session reuse
+    reuse_sessions = true
+
+    ## Maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path
+    depth = 10
+
+    ## Which versions are to be supported
+    versions = [tlsv1.3, tlsv1.2]
+
+    ## TLS cipher suite names
+    ## Note: By default, all available suites are supported, you do not need to set this
+    ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+
+    ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
+    secure_renegotiate = true
+
+    ## Log level for SSL communication
+    ## Type: emergency | alert | critical | error | warning | notice | info | debug | none | all
+    log_level = notice
+
+    ## Hibernate the SSL process after idling for amount of time reducing its memory footprint
+    hibernate_after = 5s
+
+    ## Forces the cipher to be set based on the server-specified order instead of the client-specified order
+    honor_cipher_order = true
+
+    ##  Setting this to false to disable client-initiated renegotiation
+    client_renegotiation = true
+
+    ## Maximum time duration allowed for the handshake to complete
+    handshake_timeout = 15s
+}

examples/listeners.tcp.conf.example

@@ -0,0 +1,78 @@
+##--------------------------------------------------------------------
+## TCP Listener
+##
+## Add a TCP Listener
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: Modifying the 'tcpname' to what you need
+listeners.tcp.tcpname {
+    ## false to disable this
+    enable = true
+
+    ## Port or Address to listen on
+    bind = 1883 ## or with an IP e.g. "127.0.0.1:1883"
+
+    ## Enable the Proxy Protocol V1/2 if the EMQX cluster is deployed behind HAProxy or Nginx
+    proxy_protocol = false
+
+    ## Timeout for proxy protocol
+    proxy_protocol_timeout = 8
+
+    ## When publishing or subscribing, prefix all topics with a mountpoint string
+    mountpoint = "mqtt" ## Do not set this unless you know what is it for
+
+    ## Client authentication
+    ## Type:
+    ##   - true :: enable
+    ##   - false :: disable
+    ##   - quick_deny_anonymous :: denied immediately without if username is not provided
+    enable_authn = true
+
+    ## The access control rules for this listener
+    ## Type: See: https://github.com/emqtt/esockd#allowdeny
+    access_rules = ["allow all"]
+
+    ## Socket acceptor pool size for TCP protocols
+    acceptors = 16
+
+    ## Maximum number of simultaneous connections
+    ## Type: infinity | Integer
+    max_connections = infinity
+
+    ## TCP backlog defines the maximum length that the queue of pending connections can grow to
+    backlog = 1024
+
+    ## The TCP send timeout for the connections
+    send_timeout = 15s
+
+    ## Timeout for proxy protocol
+    send_timeout_close = true
+
+    ## The TCP receive buffer (OS kernel) for the connections
+    recbuf = 2KB
+
+    ## The TCP send buffer (OS kernel) for the connections
+    sndbuf = 4KB
+
+    ## The size of the user-space buffer used by the driver
+    buffer = 4KB
+
+    ## The socket is set to a busy state when the amount of data queued internally by the VM socket implementation reaches this limit
+    high_watermark = 1MB
+
+    ## The TCP_NODELAY flag for the connections
+    nodelay = true
+
+    ## The SO_REUSEADDR flag for the connections
+    reuseaddr = true
+
+    ## Enable TCP keepalive for MQTT connections over TCP or SSL
+    ## Type: three comma separated numbers in the format of 'Idle,Interval,Probes'
+    ##    - Idle: The number of seconds a connection needs to be idle before the server begins to send out keep-alive probes (Linux default 7200).
+    ##    - Interval: The number of seconds between TCP keep-alive probes (Linux default 75).
+    ##    - Probes: The maximum number of TCP keep-alive probes to send before giving up and killing the connection if no response is obtained from the other end (Linux default 9).
+    ## For example "240,30,5" means: EMQX should start sending TCP keepalive probes after the connection is in idle for 240 seconds, and the probes are sent every 30 seconds until a response is received from the MQTT client, if it misses 5 consecutive responses, EMQX should close the connection
+    keepalive = "none"
+}

examples/listeners.ws.conf.example

@@ -0,0 +1,62 @@
+##--------------------------------------------------------------------
+## WebSocket Listener
+##
+## Add a WebSocket Listener
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## The WebSocket listener supports all the fields listed in listeners.tcp.conf.example
+## only the WebSocket-specific fields are shown here
+
+## Note: Modifying the 'wsname' to what you need
+listeners.ws.wsname {
+    ## for to disable this
+    enable = true
+
+    ## Port or Address to listen on
+    bind = "0.0.0.0:8083" # or just a port number, e.g. 8083
+
+    ## WebSocket's MQTT protocol path
+    ## Type: String
+    ##   For Example:
+    ##     with the default value, the address of EMQX Broker's WebSocket is: ws://8083/mqtt
+    mqtt_path = "/mqtt"
+
+    ## Whether a WebSocket message is allowed to contain multiple MQTT packets
+    ## Type: single | multiple
+    mqtt_piggyback = multiple
+
+    ## If true, compress WebSocket messages using zlib
+    compress = false
+
+    ## Close transport-layer connections from the clients that have not sent MQTT CONNECT message within this interval
+    idle_timeout = 7200s
+
+    ## The maximum length of a single MQTT packet
+    ## Type: infinity | Integer
+    max_frame_size = infinity
+
+    ## If true, the server will return an error when the client does not carry the Sec-WebSocket-Protocol field
+    fail_if_no_subprotocol = true
+
+    ## Comma-separated list of supported subprotocols
+    ## Type: Comma Separated List
+    supported_subprotocols = "mqtt, mqtt-v3, mqtt-v3.1.1, mqtt-v5"
+
+    ## If true, origin HTTP header will be validated against the list of allowed origins configured in check_origins parameter
+    check_origin_enable = false
+
+    ## If false and check_origin_enable is true, the server will reject requests that don't have origin HTTP header
+    allow_origin_absence = true
+
+    ## List of allowed origins
+    ## Type: Comma Separated List
+    check_origins = "http://localhost:18083, http://127.0.0.1:18083"
+
+    ## HTTP header used to pass information about the client IP address
+    proxy_address_header = "x-forwarded-for"
+
+    ## The maximum length of a single MQTT packet
+    proxy_port_header = "x-forwarded-port"
+}

examples/listeners.wss.conf.example

@@ -0,0 +1,64 @@
+##--------------------------------------------------------------------
+## WSS Listener
+##
+## Add a WSS Listener
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## The WSS listener supports all the fields listed in listeners.ws.conf.example
+## only the WSS-specific fields are shown here
+
+## Note: Modifying the 'wssname' to what you need
+listeners.wss.wssname {
+    ## false to disable this
+    enable = true
+
+    ## Port or Address to listen on
+    ## Default: 8084
+    bind = 8084 ## or with an IP, e.g. "127.0.0.1:8084"
+
+    ## PEM format certificates chain file
+    certfile = "data/certs/cert.pem"
+
+    ## PEM format private key file
+    keyfile = "data/certs/key.pem"
+
+    ## Enable or disable peer verification
+    verify = verify_none  ## use verify_peer to enable
+
+    ## if `verify' is ebabled, whit true, the connection fails if the client does not have a certificate to send
+    fail_if_no_peer_cert = false
+
+    ## Enable TLS session reuse
+    reuse_sessions = true
+
+    ## Maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path
+    depth = 10
+
+    ## Which versions are to be supported
+    versions = [tlsv1.3, tlsv1.2]
+
+    ## TLS cipher suite names
+    ## Note: By default, all available suites are supported, you do not need to set this
+    ciphers = ["TLS_AES_256_GCM_SHA384","TLS_AES_128_GCM_SHA256"]
+
+    ## Allows a client and a server to renegotiate the parameters of the SSL connection on the fly
+    secure_renegotiate = true
+
+    ## Log level for SSL communication
+    ## Type: emergency | alert | critical | error | warning | notice | info | debug | none | all
+    log_level = notice
+
+    ## Hibernate the SSL process after idling for amount of time reducing its memory footprint
+    hibernate_after = 5s
+
+    ## Forces the cipher to be set based on the server-specified order instead of the client-specified order
+    honor_cipher_order = true
+
+    ##  Setting this to false to disable client-initiated renegotiation
+    client_renegotiation = true
+
+    ## Maximum time duration allowed for the handshake to complete
+    handshake_timeout = 15s
+}

examples/log.console.conf.example

@@ -0,0 +1,27 @@
+##--------------------------------------------------------------------
+## Log
+##
+## Configure the log output location, log level, log file storage path, and parameters
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+log.console {
+    ## set true to enable this
+    enable = false
+
+    ## Log level
+    ## Type: debug | info | notice | warning | error | critical | alert | emergency
+    level = warning
+
+    ## Log formatter, text for free text, and json for structured logging
+    ## Type: text | json
+    formatter = text
+
+    ## Time offset for formatting the timestamp
+    ## Type:
+    ##   - system :: local system time
+    ##   - utc :: UTC time
+    ##   - +-[hh]:[mm]: user specified time offset, such as "-02:00" or "+00:00" Defaults to: system
+    time_offset = system
+}

examples/log.file.conf.example

@@ -0,0 +1,38 @@
+##--------------------------------------------------------------------
+## Log
+##
+## Configure the log output location, log level, log file storage path, and parameters
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## The default-enabled log handler can use all the above fields listed fields
+log.file {
+    ## use false to disable this
+    enable = true
+
+    ## Log level
+    ## Type: debug | info | notice | warning | error | critical | alert | emergency
+    level = warning
+
+    ## Log formatter, text for free text, and json for structured logging
+    ## Type: text | json
+    formatter = text
+
+    ## Time offset for formatting the timestamp
+    ## Type:
+    ##   - system :: local system time
+    ##   - utc :: UTC time
+    ##   - +-[hh]:[mm]: user specified time offset, such as "-02:00" or "+00:00" Defaults to: system
+    time_offset = system
+
+    ## Maximum number of log files
+    ## Type: Range from 1 to 128
+    rotation_count = 10
+
+    ## This parameter controls log file rotation
+    ## Type:
+    ##  - infinity :: the log file will grow indefinitely
+    ##  - ByteSize :: the log file will be rotated once it reaches this value in bytes
+    rotation_size = "50MB"
+}

examples/mqtt.conf.example

@@ -0,0 +1,113 @@
+##--------------------------------------------------------------------
+## MQTT
+##
+##  MQTT configuration
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+mqtt {
+    ## After the TCP connection is established,
+    ## if the MQTT CONNECT packet from the client is not received within the time specified by idle_timeout, the connection will be disconnected
+    ## Type:
+    ##   - infinity :: Never disconnect
+    ##   - Time Duration :: The idle time
+    idle_timeout = 15s
+
+    ## Maximum MQTT packet size allowed
+    max_packet_size = 1MB
+
+    ## Maximum allowed length of MQTT Client ID
+    ## Type: Rnage from 23 to 65535
+    max_clientid_len = 65535
+
+    ## Maximum topic levels allowed
+    ## Type: Range from 1 to 65535
+    max_topic_levels = 128
+
+    ## Maximum QoS allowed
+    max_qos_allowed = 2
+
+    ## Maximum topic alias, 0 means no topic alias supported
+    ## Type: Range from 0 to 65535
+    max_topic_alias = 65535
+
+    ## Whether to enable support for MQTT retained message
+    retain_available = true
+
+    ## Whether to enable support for MQTT wildcard subscription
+    wildcard_subscription = true
+
+    ## Whether to enable support for MQTT shared subscription
+    shared_subscription = true
+
+    ## Whether to enable support for MQTT exclusive subscription
+    exclusive_subscription = false
+
+    ## Ignore loop delivery of messages for MQTT v3.1.1/v3.1.0, similar to No Local subscription option in MQTT 5.0
+    ignore_loop_deliver = false
+
+    ## Parse MQTT messages in strict mode.
+    ## When set to true, invalid utf8 strings in for example client ID, topic name, etc. will cause the client to be disconnected
+    strict_mode = false
+
+    ## Specify the response information returned to the client
+    response_information  = ""
+
+    ## The keep alive that EMQX requires the client to use
+    ## Type:
+    ##   - disabled :: the keep alive specified by the client will be used
+    ##   - Integer :: Keepalive time, only applicable to clients using MQTT 5.0 protocol
+    server_keepalive = disabled
+
+    ## Keep-Alive Timeout = Keep-Alive interval × Keep-Alive Multiplier
+    keepalive_multiplier = 1.5
+
+    ## Maximum number of subscriptions allowed per client
+    ## Type: infinity | Integer
+    max_subscriptions = infinity
+
+    ## Force upgrade of QoS level according to subscription
+    upgrade_qos = false
+
+    ## Maximum number of QoS 1 and QoS 2 messages that are allowed to be delivered simultaneously before completing the acknowledgment
+    ## Type: Range from 1 to 65535
+    max_inflight = 32
+
+    ## Retry interval for QoS 1/2 message delivering
+    retry_interval = 30s
+
+    ## For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL
+    ## Type: infinity | Integer
+    max_awaiting_rel = 100
+
+    ## For client to broker QoS 2 message, the time limit for the broker to wait before the PUBREL message is received
+    await_rel_timeout = 300s
+
+    ## Specifies how long the session will expire after the connection is disconnected, only for non-MQTT 5.0 connections
+    session_expiry_interval = 2h
+
+    ## Maximum queue length. Enqueued messages when persistent client disconnected, or inflight window is full
+    ## Type: infinity | Integer
+    max_mqueue_len = 1000
+
+    ## Specifies whether to store QoS 0 messages in the message queue while the connection is down but the session remains
+    mqueue_store_qos0 = true
+
+    ## Whether to user Client ID as Username
+    use_username_as_clientid = false
+
+    ## Use the CN, DN field in the peer certificate or the entire certificate content as Username
+    ## Type:
+    ##   - disabled
+    ##   - cn :: CN field of the certificate
+    ##   - dn :: DN field of the certificate
+    ##   - crt :: the content of the DER or PEM certificate
+    ##   - pem :: PEM format content converted from DER certificate content
+    ##   - md5 :: the MD5 value of the content of the DER or PEM certificate
+    peer_cert_as_username = disabled
+
+    ## Use the CN, DN field in the peer certificate or the entire certificate content as Client ID
+    ## Type: See the above
+    peer_cert_as_clientid = disabled
+ }

examples/node.conf.example

@@ -0,0 +1,43 @@
+##--------------------------------------------------------------------
+## Node
+##
+## configuring for current EMQX node
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: all fields in this section are immutable after EMQX started, and most of the time you only need to modify the value for the name and cookie.
+node {
+    ## The actions triggered when the alarm is activated
+    ## Type: Formatted String
+    ##   Format: any_name@any_domain or an_name@any_ip
+    ##   Note: Make sure the IP resolve from the domain is deterministic and unique and never change
+    name = "emqx@127.0.0.1"
+
+    ## Secret cookie is a random string that should be the same on all nodes in the given EMQX cluster, but unique per EMQX cluster
+    cookie = "Yzc0NGExM2RjYzYxYzM0YzQ5MWQ0NmI1NWM0MWRhMzY4NzgxYmFkMmI2MWJjZWQ5NTQzYTMxNjE1ODVmYmJmMyAgLQo="
+
+    ## Select a node role
+    ## Type:
+    ##   - core :: nodes provide durability of the data, and take care of writes
+    ##   - replicant :: nodes are ephemeral worker nodes
+    role = core
+
+    ## Maximum number of simultaneously existing processes for this Erlang system
+    ## Type: Range from 1024 to 134217727
+    process_limit = 2097152
+
+    ## Maximum number of simultaneously existing ports for this Erlang system
+    ## Type: Range from 1024 to 134217727
+    max_ports = 1048576
+
+    ## Erlang's distribution buffer busy limit in kilobytes
+    ## Type: Range from 1 to 2097152
+    dist_buffer_size = 8192
+
+    ## Path to the persistent data directory
+    data_dir = "var/emqx/data"
+
+    ## Type: Periodic garbage collection interval
+    global_gc_interval = "15m"
+}

examples/overload_protection.conf.example

@@ -0,0 +1,25 @@
+##--------------------------------------------------------------------
+## Overload Protection
+##
+## Monitoring the load of the system and temporarily disable some features when the load is high
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: Do not modify this unless you know what this is for
+overload_protection {
+    ## set true to enable this
+    enable = false
+
+    ## Maximum duration of delay for background task execution during high load conditions
+    backoff_delay = 1
+
+    ## When at high load, skip forceful GC
+    backoff_gc = false
+
+    ## When at high load, skip process hibernation
+    backoff_hibernation = true
+
+    ## When at high load, close new incoming connections
+    backoff_new_conn = true
+}

examples/plugin.conf.example

@@ -0,0 +1,27 @@
+##--------------------------------------------------------------------
+## Plugin
+##
+## Manage EMQX plugins
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+plugin {
+    ## Plugins declaration
+    ## Note: The plugins are started in the defined order
+    states = [
+        {
+            ## Name and version of this plugin
+            ## Type: Formatted String
+            ##     Format: {name}-{version}
+            ##     Note: name and version should be what it is in the plugin application
+            name_vsn = "my_acl-0.1.0",
+
+            enable = true ## enable this plugin
+        },
+        {name_vsn = "my_rule-0.1.1", enable = false}
+    ]
+
+    ## The installation directory for the external plugins
+    install_dir = "plugins"
+}

examples/prometheus.conf.example

@@ -0,0 +1,28 @@
+##--------------------------------------------------------------------
+## Prometheus
+##
+## Settings for reporting metrics to Prometheus
+##--------------------------------------------------------------------
+
+prometheus {
+    ## URL of Prometheus server
+    push_gateway_server = "http://127.0.0.1:9091"
+
+    ## Data reporting interval
+    interval = 15s
+
+    ## A HTTP Headers when pushing to Push Gateway.
+    headers = {
+        Authorization = "some-authz-tokens",
+        Connection = "keep-alive"
+    }
+
+    ## Job Name that is pushed to the Push Gateway.
+    ## Available variable:
+    ## - ${name}: Name of EMQX node
+    ## - ${host}: Host name of EMQX node
+    job_name = "${name}/instance/${name}~${host}"
+
+    ## set true to enable this
+    enable = false
+}

examples/psk_authentication.conf.example

@@ -0,0 +1,21 @@
+##--------------------------------------------------------------------
+## Pre-Shared Keys authentication
+##
+## Config to enable TLS-PSK authentication
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+psk_authentication {
+    ## set true to enable TLS PSK support
+    enable = false
+
+    ## If init_file is specified, EMQX will import PSKs from the file into the built-in database at startup for use by the runtime
+    init_file = "psk"
+
+    ## The separator between PSKIdentity and SharedSecret in the PSK file
+    separator = ":"
+
+    ## The size of each chunk used to import to the built-in database from PSK file
+    chunk_size = 50
+ }

examples/retainer.conf.example

@@ -0,0 +1,40 @@
+##--------------------------------------------------------------------
+## Retainer
+##
+## Configuration related to handling PUBLISH packets with a retain flag set to 1
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+retainer {
+    ## set to false to disable this
+    enable = true
+
+    ## Message retention time. 0 means message will never be expired
+    msg_expiry_interval = 0s
+
+    ## Periodic interval for cleaning up expired messages. Never clear if the value is 0
+    msg_clear_interval = 0s
+
+    ## Maximum retained message size
+    max_payload_size = 1MB
+
+    ## When the retained flag of the PUBLISH message is set and Payload is empty, whether to continue to publish the message
+    stop_publish_clear_msg = false
+
+    ## Maximum retained messages delivery rate per session
+    deliver_rate = "1000/s"
+
+    ## Retained messages store backend
+    backend {
+      ## Backend type
+      type = built_in_database
+
+      ## Specifies whether the messages are stored in RAM or persisted on disc
+      ## Type: enum: ram | disc
+      storage_type = ram
+
+      ## Maximum number of retained messages. 0 means no limit
+      max_retained_messages = 0
+     }
+ }

examples/rpc-with-ssl.conf.example

@@ -0,0 +1,76 @@
+##--------------------------------------------------------------------
+## RPC With SSL
+## See rpc-with-tcp.conf.example for RPC with TCP
+## EMQX inter-broker communication
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: Most of the time the default config should work
+##   you do not need to modify it unless you know what it is for
+rpc {
+    ## Communication mode
+    ## Type: async | sync
+    mode = async
+
+    ## Transport protocol used for inter-broker communication
+    ## Type: tcp | ssl
+    protocol = ssl
+
+    ## The maximum number of batch messages sent in asynchronous mode
+    ## Type: Integer
+    async_batch_size = 256
+
+    ## Port discovery strategy
+    ## Type:
+    ##   - manual :: discover ports by tcp_server_port
+    ##   - stateless :: discover ports in a stateless manner, using the following algorithm:
+    ##       If node name is emqxN@127.0.0.1, where the N is an integer, then the listening port will be 5370 + N
+    port_discovery = stateless
+
+    ## Listening port used by RPC local service
+    ssl_server_port = 5369
+
+    ## Set the maximum number of RPC communication channels initiated by this node to each remote node
+    ## Type: Range from 1 to 256
+    tcp_client_num = 10
+
+    ## Timeout for establishing an RPC connection
+    connect_timeout = 5s
+
+    ## Path to TLS certificate file used to validate identity of the cluster nodes
+    certfile = "data/cert.pem"
+
+    ## Path to the private key file
+    keyfile = "data/key.pem"
+
+    ## Path to certification authority TLS certificate file
+    cacertfile = "data/cacert.pem"
+
+    ## Timeout for sending the RPC request
+    send_timeout = 5s
+
+    ## Timeout for the remote node authentication
+    authentication_timeout = 5s
+
+    ## Timeout for the reply to a synchronous RPC
+    call_receive_timeout = 15s
+
+    ## How long the connections between the brokers should remain open after the last message is sent
+    socket_keepalive_idle = 15m
+
+    ## The interval between keepalive messages
+    socket_keepalive_interval = 75s
+
+    ## How many times the keepalive probe message can fail to receive a reply until the RPC connection is considered lost
+    socket_keepalive_count = 9
+
+    ## TCP sending buffer size
+    socket_sndbuf = 1MB
+
+    ## TCP receiving buffer size
+    socket_recbuf = 1MB
+
+    ## Socket buffer size in user mode
+    socket_buffer = 1MB
+ }

examples/rpc-with-tcp.conf.example

@@ -0,0 +1,67 @@
+##--------------------------------------------------------------------
+## RPC With TCP
+## See rpc-with-ssl.conf.example for RPC with SSL
+## EMQX inter-broker communication
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+## Note: Most of the time the default config should work
+##   you do not need to modify it unless you know what it is for
+rpc {
+    ## Communication mode
+    ## Type: sync | async
+    mode = async
+
+    ## Transport protocol used for inter-broker communication
+    ## Type: tcp | ssl
+    protocol = tcp
+
+    ## The maximum number of batch messages sent in asynchronous mode
+    ## Type: Integer
+    async_batch_size = 256
+
+    ## Port discovery strategy
+    ## Type:
+    ##   - manual :: discover ports by tcp_server_port
+    ##   - stateless :: discover ports in a stateless manner, using the following algorithm:
+    ##       If node name is emqxN@127.0.0.1, where the N is an integer, then the listening port will be 5370 + N
+    port_discovery = stateless
+
+    ## Listening port used by RPC local service
+    tcp_server_port = 5369
+
+    ## Set the maximum number of RPC communication channels initiated by this node to each remote node
+    ## Type: Range from 1 to 256
+    tcp_client_num = 10
+
+    ## Timeout for establishing an RPC connection
+    connect_timeout = 5s
+
+    ## Timeout for sending the RPC request
+    send_timeout = 5s
+
+    ## Timeout for the remote node authentication
+    authentication_timeout = 5s
+
+    ## Timeout for the reply to a synchronous RPC
+    call_receive_timeout = 15s
+
+    ## How long the connections between the brokers should remain open after the last message is sent
+    socket_keepalive_idle = 15m
+
+    ## The interval between keepalive messages
+    socket_keepalive_interval = 75s
+
+    ## How many times the keepalive probe message can fail to receive a reply until the RPC connection is considered lost
+    socket_keepalive_count = 9
+
+    ## TCP sending buffer size
+    socket_sndbuf = 1MB
+
+    ## TCP receiving buffer size
+    socket_recbuf = 1MB
+
+    ## Socket buffer size in user mode
+    socket_buffer = 1MB
+ }

examples/slow_subs.conf.example

@@ -0,0 +1,28 @@
+##--------------------------------------------------------------------
+## Slow Subscribers Statistics
+##
+## Count subscribers with topics whose transfer time exceeds the threshold
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+slow_subs {
+    ## Stats Threshold
+    threshold = 500ms
+
+    ## Expire time of the record which in Top-K record
+    expire_interval = 300ms
+
+    ## Maximum number of Top-K record
+    top_k_num = 10
+
+    ## Stats Type
+    ## Value:
+    ## - whole: from the time the message arrives at EMQX until the message transmission completes
+    ## - internal: from when the message arrives at EMQX until when EMQX starts delivering the message
+    ## - response: from the time EMQX starts delivering the message until the message transmission completes
+    stats_type = whole
+
+    ## use true to enable this
+    enable = false
+}

examples/sys_topics.conf.example

@@ -0,0 +1,25 @@
+##--------------------------------------------------------------------
+## System Topic
+##
+## Publishing client lifecycle events to "$SYS" topics
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+sys_topics {
+    ## Time interval of publishing `$SYS` messages
+    sys_msg_interval = 1m
+
+    ## Time interval for publishing following heartbeat messages:
+    ##   - `$SYS/brokers/<node>/uptime`
+    ##   - `$SYS/brokers/<node>/datetime`
+    sys_heartbeat_interval = 30s
+
+    ## Client events messages toggle
+    sys_event_messages = {
+        client_connected = true
+        client_disconnected = true
+        client_subscribed = false
+        client_unsubscribed = false
+    }
+}

examples/sysmon.os.conf.example

@@ -0,0 +1,30 @@
+##--------------------------------------------------------------------
+## System Monitoring For System
+##
+## System monitoring and introspection
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+sysmon.os {
+    ## Time interval for the periodic CPU check
+    cpu_check_interval = "60s"
+
+    ## For how much system cpu can be used before the corresponding alarm is raised
+    cpu_high_watermark = "80%"
+
+    ## For how much system cpu can be used before the corresponding alarm is cleared
+    cpu_low_watermark = "60%"
+
+    ## Time interval for the periodic memory check
+    ## Type:
+    ##   - disabled :: Never check
+    ##   - Time Duration :: The time period
+    mem_check_interval = "60s"
+
+    ## For how much system memory can be allocated before the corresponding alarm is raised
+    sysmem_high_watermark = "70%"
+
+    ## For how much system memory can be allocated by one Erlang process before the corresponding alarm is raised
+    procmem_high_watermark = "5%"
+}

examples/sysmon.vm.conf.example

@@ -0,0 +1,42 @@
+##--------------------------------------------------------------------
+## System Monitoring For Erlang VM
+##
+## System monitoring and introspection
+##--------------------------------------------------------------------
+## Note: This is an example of how to configure this feature
+##       you should copy and paste the below data into the emqx.conf for working
+
+sysmon.vm {
+    ## Time interval for the periodic process limit check
+    process_check_interval = 30s
+
+    ## For how many processes can simultaneously exist at the local node before the corresponding alarm is raised
+    process_high_watermark = "80%"
+
+    ## For how many processes can simultaneously exist at the local node before the corresponding alarm is cleared
+    process_low_watermark = "60%"
+
+    ## Generated an alarm when an Erlang process spends a long time to perform garbage collection
+    ## Type:
+    ##   - disabled :: Never alarm
+    ##   - Time During :: The maximum GC time for generating an alarm
+    long_gc = 100ms
+
+    ## Generating an alarm is generated when the Erlang VM detect a task scheduled for too long
+    ## Type:
+    ##   - disabled :: Never alarm
+    ##   - Time During :: The maximum schedule time for generating an alarm
+    long_schedule = 240ms
+
+    ## Generating an alarm when an Erlang process consumed a large amount of memory for its heap space
+    ## Type:
+    ##   - disabled :: Never alarm
+    ##   - ByteSize :: The maximum heap size for generating an alarm
+    large_heap = 32M
+
+    ## Generating an alarm when the RPC connection is overloaded
+    busy_dist_port = true
+
+    ## Generating an alarm when a port (e.g. TCP socket) is overloaded
+    busy_port = true
+}

rel/i18n/emqx_prometheus_schema.hocon

@@ -4,7 +4,7 @@ enable.desc:
 """Turn Prometheus data pushing on or off"""
 
 headers.desc:
-"""A list of HTTP Headers when pushing to Push Gateway.<br/>
+"""A HTTP Headers when pushing to Push Gateway.<br/>
 For example, <code> { Authorization = "some-authz-tokens"}</code>"""
 
 interval.desc: