# [NATS Streaming](https://nats.io): A high-performance cloud native messaging streaming system. %%LOGO%% `nats-streaming` is a high performance streaming server for the NATS Messaging System. # Backward compatibility note Note that the Streaming server itself is backward compatible with previous releases, however, v0.15.0+ now embeds a NATS Server 2.0, which means that if you run with the embedded NATS server and want to route it to your existing v0.14.3- servers, it will fail due to NATS Server routing protocol change. You can however use v0.15.0+ and connect it to existing NATS cluster and therefore have a mix of v0.15.0 and v0.14.3- streaming servers. # Windows Docker images Due to restrictions on how the Windows Docker Image is built, running the image without argument will run the NATS Streaming server with memory based store on port 4222 and the monitoring port 8222. If you need to specify any additional argument, or modify these options, you need to specify the executable name as this: ```bash $ docker run -p 4223:4223 -p 8223:8223 %%IMAGE%% nats-streaming-server -p 4223 -m 8223 ``` If you need to specify the entrypoint: ```bash $ docker run --entrypoint c:/nats-streaming-server/nats-streaming-server -p 4222:4222 -p 8222:8222 %%IMAGE%% ``` # Non Windows Docker images If you need to provide arguments to the NATS Streaming server, just pass them to the command line. For instance, to change the listen and monitoring port to 4223 and 8223 respectively: ```bash $ docker run -p 4223:4223 -p 8223:8223 %%IMAGE%% -p 4223 -m 8223 ``` If you need to specify the entrypoint: ```bash $ docker run --entrypoint /nats-streaming-server -p 4222:4222 -p 8222:8222 %%IMAGE%% ``` # Example usage ```bash # Run a NATS Streaming server # Each server exposes multiple ports # 4222 is for clients. # 8222 is an HTTP management port for information reporting. # # To actually publish the ports when running the container, use the Docker port mapping # flag "docker run -p :" to publish and map one or more ports, # or the -P flag to publish all exposed ports and map them to high-order ports. # # This should not be confused with the NATS Streaming Server own -p parameter. # For instance, to run the NATS Streaming Server and have it listen on port 4444, # you would have to run like this: # # docker run -p 4444:4444 %%IMAGE%% -p 4444 # # Or, if you want to publish the port 4444 as a different port, for example 5555: # # docker run -p 5555:4444 %%IMAGE%% -p 4444 # # Check "docker run" for more information. $ docker run -d -p 4222:4222 -p 8222:8222 %%IMAGE%% ``` Output that you would get if you had started with `-ti` instead of `d` (for daemon): ```bash [1] 2019/08/15 21:11:10.187317 [INF] STREAM: Starting nats-streaming-server[test-cluster] version 0.16.0 [1] 2019/08/15 21:11:10.187358 [INF] STREAM: ServerID: oDH4imUgj6JcrVpKyRgXn6 [1] 2019/08/15 21:11:10.187361 [INF] STREAM: Go version: go1.11.13 [1] 2019/08/15 21:11:10.187362 [INF] STREAM: Git commit: [27593aa] [1] 2019/08/15 21:11:10.188160 [INF] Starting nats-server version 2.0.4 [1] 2019/08/15 21:11:10.188184 [INF] Git commit [c8ca58e] [1] 2019/08/15 21:11:10.188280 [INF] Starting http monitor on 0.0.0.0:8222 [1] 2019/08/15 21:11:10.188335 [INF] Listening for client connections on 0.0.0.0:4222 [1] 2019/08/15 21:11:10.188357 [INF] Server id is NDXR7P7KCMMWBCE2INUAAPTQX7HSXYGG65J3LDNRRX3DMC5GK66YVQJ6 [1] 2019/08/15 21:11:10.188359 [INF] Server is ready [1] 2019/08/15 21:11:10.215666 [INF] STREAM: Recovering the state... [1] 2019/08/15 21:11:10.215692 [INF] STREAM: No recovered state [1] 2019/08/15 21:11:10.468863 [INF] STREAM: Message store is MEMORY [1] 2019/08/15 21:11:10.468940 [INF] STREAM: ---------- Store Limits ---------- [1] 2019/08/15 21:11:10.468946 [INF] STREAM: Channels: 100 * [1] 2019/08/15 21:11:10.468948 [INF] STREAM: --------- Channels Limits -------- [1] 2019/08/15 21:11:10.468951 [INF] STREAM: Subscriptions: 1000 * [1] 2019/08/15 21:11:10.468954 [INF] STREAM: Messages : 1000000 * [1] 2019/08/15 21:11:10.468956 [INF] STREAM: Bytes : 976.56 MB * [1] 2019/08/15 21:11:10.468959 [INF] STREAM: Age : unlimited * [1] 2019/08/15 21:11:10.468961 [INF] STREAM: Inactivity : unlimited * [1] 2019/08/15 21:11:10.468964 [INF] STREAM: ---------------------------------- ``` To use a file based store instead, you would run: ```bash $ docker run -d -p 4222:4222 -p 8222:8222 %%IMAGE%% -store file -dir datastore [1] 2019/08/15 21:14:25.981900 [INF] STREAM: Starting nats-streaming-server[test-cluster] version 0.16.0 [1] 2019/08/15 21:14:25.981974 [INF] STREAM: ServerID: P3SrypfLQVr1CuGVDMJB2d [1] 2019/08/15 21:14:25.981977 [INF] STREAM: Go version: go1.11.13 [1] 2019/08/15 21:14:25.981979 [INF] STREAM: Git commit: [27593aa] [1] 2019/08/15 21:14:25.983009 [INF] Starting nats-server version 2.0.4 [1] 2019/08/15 21:14:25.983034 [INF] Git commit [c8ca58e] [1] 2019/08/15 21:14:25.983098 [INF] Listening for client connections on 0.0.0.0:4222 [1] 2019/08/15 21:14:25.983120 [INF] Server id is NCOCGHHMLJOYY3OASYTZ443DNCAZ7H7OLKM5KMQQBBGS2DHSSBUWJMP7 [1] 2019/08/15 21:14:25.983123 [INF] Server is ready [1] 2019/08/15 21:14:26.012490 [INF] STREAM: Recovering the state... [1] 2019/08/15 21:14:26.012716 [INF] STREAM: No recovered state [1] 2019/08/15 21:14:26.266161 [INF] STREAM: Message store is FILE [1] 2019/08/15 21:14:26.266260 [INF] STREAM: Store location: datastore [1] 2019/08/15 21:14:26.266286 [INF] STREAM: ---------- Store Limits ---------- [1] 2019/08/15 21:14:26.266326 [INF] STREAM: Channels: 100 * [1] 2019/08/15 21:14:26.266332 [INF] STREAM: --------- Channels Limits -------- [1] 2019/08/15 21:14:26.266336 [INF] STREAM: Subscriptions: 1000 * [1] 2019/08/15 21:14:26.266339 [INF] STREAM: Messages : 1000000 * [1] 2019/08/15 21:14:26.266384 [INF] STREAM: Bytes : 976.56 MB * [1] 2019/08/15 21:14:26.266386 [INF] STREAM: Age : unlimited * [1] 2019/08/15 21:14:26.266388 [INF] STREAM: Inactivity : unlimited * [1] 2019/08/15 21:14:26.266389 [INF] STREAM: ---------------------------------- ``` You can also connect to a remote NATS Server running in a docker image. First, run NATS Server: ```bash $ docker run -d --name=nats-main -p 4222:4222 -p 6222:6222 -p 8222:8222 nats ``` Now, start the Streaming server and link it to the above docker image: ```bash $ docker run -d --link nats-main %%IMAGE%% -store file -dir datastore -ns nats://nats-main:4222 [1] 2019/08/15 21:14:50.262771 [INF] STREAM: Starting nats-streaming-server[test-cluster] version 0.16.0 [1] 2019/08/15 21:14:50.262812 [INF] STREAM: ServerID: od2KRGkM6JSQQkqQ30naBo [1] 2019/08/15 21:14:50.262815 [INF] STREAM: Go version: go1.11.13 [1] 2019/08/15 21:14:50.262817 [INF] STREAM: Git commit: [27593aa] [1] 2019/08/15 21:14:50.291143 [INF] STREAM: Recovering the state... [1] 2019/08/15 21:14:50.291269 [INF] STREAM: No recovered state [1] 2019/08/15 21:14:50.545165 [INF] STREAM: Message store is FILE [1] 2019/08/15 21:14:50.545215 [INF] STREAM: Store location: datastore [1] 2019/08/15 21:14:50.545300 [INF] STREAM: ---------- Store Limits ---------- [1] 2019/08/15 21:14:50.545318 [INF] STREAM: Channels: 100 * [1] 2019/08/15 21:14:50.545322 [INF] STREAM: --------- Channels Limits -------- [1] 2019/08/15 21:14:50.545325 [INF] STREAM: Subscriptions: 1000 * [1] 2019/08/15 21:14:50.545362 [INF] STREAM: Messages : 1000000 * [1] 2019/08/15 21:14:50.545367 [INF] STREAM: Bytes : 976.56 MB * [1] 2019/08/15 21:14:50.545370 [INF] STREAM: Age : unlimited * [1] 2019/08/15 21:14:50.545372 [INF] STREAM: Inactivity : unlimited * [1] 2019/08/15 21:14:50.545375 [INF] STREAM: ---------------------------------- ``` Notice that the output shows that the NATS Server was not started, as opposed to the first output. # Commandline Options ```bash Streaming Server Options: -cid, --cluster_id Cluster ID (default: test-cluster) -st, --store Store type: MEMORY|FILE|SQL (default: MEMORY) --dir For FILE store type, this is the root directory -mc, --max_channels Max number of channels (0 for unlimited) -msu, --max_subs Max number of subscriptions per channel (0 for unlimited) -mm, --max_msgs Max number of messages per channel (0 for unlimited) -mb, --max_bytes Max messages total size per channel (0 for unlimited) -ma, --max_age Max duration a message can be stored ("0s" for unlimited) -mi, --max_inactivity Max inactivity (no new message, no subscription) after which a channel can be garbage collected (0 for unlimited) -ns, --nats_server Connect to this external NATS Server URL (embedded otherwise) -sc, --stan_config Streaming server configuration file -hbi, --hb_interval Interval at which server sends heartbeat to a client -hbt, --hb_timeout How long server waits for a heartbeat response -hbf, --hb_fail_count Number of failed heartbeats before server closes the client connection --ft_group Name of the FT Group. A group can be 2 or more servers with a single active server and all sharing the same datastore -sl, --signal [=] Send signal to nats-streaming-server process (stop, quit, reopen) --encrypt Specify if server should use encryption at rest --encryption_cipher Cipher to use for encryption. Currently support AES and CHAHA (ChaChaPoly). Defaults to AES --encryption_key Encryption Key. It is recommended to specify it through the NATS_STREAMING_ENCRYPTION_KEY environment variable instead Streaming Server Clustering Options: --clustered Run the server in a clustered configuration (default: false) --cluster_node_id ID of the node within the cluster if there is no stored ID (default: random UUID) --cluster_bootstrap Bootstrap the cluster if there is no existing state by electing self as leader (default: false) --cluster_peers Comma separated list of cluster peer node IDs to bootstrap cluster state --cluster_log_path Directory to store log replication data --cluster_log_cache_size Number of log entries to cache in memory to reduce disk IO (default: 512) --cluster_log_snapshots Number of log snapshots to retain (default: 2) --cluster_trailing_logs Number of log entries to leave after a snapshot and compaction --cluster_sync Do a file sync after every write to the replication log and message store --cluster_raft_logging Enable logging from the Raft library (disabled by default) Streaming Server File Store Options: --file_compact_enabled Enable file compaction --file_compact_frag File fragmentation threshold for compaction --file_compact_interval Minimum interval (in seconds) between file compactions --file_compact_min_size Minimum file size for compaction --file_buffer_size File buffer size (in bytes) --file_crc Enable file CRC-32 checksum --file_crc_poly Polynomial used to make the table used for CRC-32 checksum --file_sync Enable File.Sync on Flush --file_slice_max_msgs Maximum number of messages per file slice (subject to channel limits) --file_slice_max_bytes Maximum file slice size - including index file (subject to channel limits) --file_slice_max_age Maximum file slice duration starting when the first message is stored (subject to channel limits) --file_slice_archive_script Path to script to use if you want to archive a file slice being removed --file_fds_limit Store will try to use no more file descriptors than this given limit --file_parallel_recovery On startup, number of channels that can be recovered in parallel --file_truncate_bad_eof Truncate files for which there is an unexpected EOF on recovery, dataloss may occur --file_read_buffer_size Size of messages read ahead buffer (0 to disable) --file_auto_sync Interval at which the store should be automatically flushed and sync'ed on disk (<= 0 to disable) Streaming Server SQL Store Options: --sql_driver Name of the SQL Driver ("mysql" or "postgres") --sql_source Datasource used when opening an SQL connection to the database --sql_no_caching Enable/Disable caching for improved performance --sql_max_open_conns Maximum number of opened connections to the database Streaming Server TLS Options: -secure Use a TLS connection to the NATS server without verification; weaker than specifying certificates. -tls_client_key Client key for the streaming server -tls_client_cert Client certificate for the streaming server -tls_client_cacert Client certificate CA for the streaming server Streaming Server Logging Options: -SD, --stan_debug= Enable STAN debugging output -SV, --stan_trace= Trace the raw STAN protocol -SDV Debug and trace STAN --syslog_name On Windows, when running several servers as a service, use this name for the event source (See additional NATS logging options below) Embedded NATS Server Options: -a, --addr Bind to host address (default: 0.0.0.0) -p, --port Use port for clients (default: 4222) -P, --pid File to store PID -m, --http_port Use port for http monitoring -ms,--https_port Use port for https monitoring -c, --config Configuration file Logging Options: -l, --log File to redirect log output -T, --logtime= Timestamp log entries (default: true) -s, --syslog Enable syslog as log method -r, --remote_syslog Syslog server addr (udp://localhost:514) -D, --debug= Enable debugging output -V, --trace= Trace the raw protocol -DV Debug and trace Authorization Options: --user User required for connections --pass Password required for connections --auth Authorization token required for connections TLS Options: --tls= Enable TLS, do not verify clients (default: false) --tlscert Server certificate file --tlskey Private key for server certificate --tlsverify= Enable TLS, verify client certificates --tlscacert Client certificate CA for verification NATS Clustering Options: --routes Routes to solicit and connect --cluster Cluster URL for solicited routes Common Options: -h, --help Show this message -v, --version Show version --help_tls TLS help. ``` # Configuration Details on how to configure further the NATS Streaming server can be found [here](https://github.com/nats-io/nats-streaming-server#configuring)