--- name: "traffic_ctl" section: "8" platform: "linux" package: "trafficserver" version: "9.2.5+ds-0+deb12u4" release: "Debian 12 (Bookworm)" platforms: ["linux"] url: "https://new.carta.tech/traffic_ctl" --- # traffic\_ctl(8) Traffic Server command line tool ## NAME traffic\_ctl - Traffic Server command line tool ## SYNOPSIS **traffic\_ctl** \[OPTIONS\] SUBCOMMAND \[OPTIONS\] ## DESCRIPTION **traffic\_ctl** is used to display and manipulate configure a running Traffic Server. **traffic\_ctl** includes a number of subcommands that control different aspects of Traffic Server: - **traffic\_ctl alarm** Display and manipulate Traffic Server alarms - **traffic\_ctl config** Manipulate and display configuration records - **traffic\_ctl metric** Manipulate performance and status metrics - **traffic\_ctl server** Stop, restart and examine the server - **traffic\_ctl storage** Manipulate cache storage - **traffic\_ctl plugin** Interact with plugins. - **traffic\_ctl host** Manipulate host status. parents for now but will be expanded to origins. To use **traffic\_ctl**, *traffic\_manager* needs to be running. ## OPTIONS - **--debug** Enable debugging output. - **-V, --version** Print version information and exit. ## SUBCOMMANDS ### traffic\_ctl alarm - **list** List all alarm events that have not been acknowledged (cleared). - **clear** Clear (acknowledge) all current alarms. - **resolve ALARM \[ALARM...\]** Clear (acknowledge) an alarm event. The arguments are a specific alarm number (e.g. ''1''), or an alarm string identifier (e.g. ''MGMT\_ALARM\_PROXY\_CONFIG\_ERROR''). ### traffic\_ctl config - **defaults \[--records\]** Display the default values for all configuration records. The --records\* flag has the same behavior as *traffic\_ctl config get --records*. - **describe RECORD \[RECORD...\]** Display all the known information about a configuration record. This includes the current and default values, the data type, the record class and syntax checking expression. - **diff \[--records\]** Display configuration records that have non-default values. The --records\* flag has the same behavior as *traffic\_ctl config get --records*. - **get \[--records\] RECORD \[RECORD...\]** Display the current value of a configuration record. - **--records** If this flag is provided, *traffic\_ctl config get* will emit results in *records.config* format. - **match \[--records\] REGEX \[REGEX...\]** Display the current values of all configuration variables whose names match the given regular expression. The *--records* flag has the same behavior as *traffic\_ctl config get* *--records*. - **reload** Initiate a Traffic Server configuration reload. Use this command to update the running configuration after any configuration file modification. If no configuration files have been modified since the previous configuration load, this command is a no-op. The timestamp of the last reconfiguration event (in seconds since epoch) is published in the *proxy.node.config.reconfigure\_time* metric. - **set RECORD VALUE** Set the named configuration record to the specified value. Refer to the *records.config* documentation for a list of the configuration variables you can specify. Note that this is not a synchronous operation. - **status** Display detailed status about the Traffic Server configuration system. This includes version information, whether the internal configuration store is current and whether any daemon processes should be restarted. ### traffic\_ctl metric - **get METRIC \[METRIC...\]** Display the current value of the specifies statistics. - **match REGEX \[REGEX...\]** Display the current values of all statistics whose names match the given regular expression. - **zero METRIC \[METRIC...\]** Reset the named statistics to zero. ### traffic\_ctl server - **restart** Shut down and immediately restart Traffic Server - **--drain** This option modifies the behavior of *traffic\_ctl server restart* such that **traffic\_server** is not shut down until the number of active client connections drops to the number given by the *proxy.config.restart.active\_client\_threshold* configuration variable. - **--manager** The default behavior of *traffic\_ctl server restart* is to restart **traffic\_server**. If this option is specified, **traffic\_manager** is also restarted. - **start** Start **traffic\_server** if it is already running. - **--clear-cache** Clear the disk cache upon startup. - **--clear-hostdb** Clear the DNS resolver cache upon startup. - **status** Show the current proxy server status, indicating if we're running or not. - **stop** Stop the running **traffic\_server** process. - **backtrace** Show a full stack trace of all the **traffic\_server** threads. ### traffic\_ctl storage - **offline PATH \[PATH ...\]** Mark a cache storage device as offline. The storage is identified by *PATH* which must match exactly a path specified in *storage.config*. This removes the storage from the cache and redirects requests that would have used this storage to other storage. This has exactly the same effect as a disk failure for that storage. This does not persist across restarts of the **traffic\_server** process. ### traffic\_ctl plugin - **msg TAG DATA** Send a message to plugins. All plugins that have hooked the *TSLifecycleHookID::TS\_LIFECYCLE\_MSG\_HOOK* will receive a callback for that hook. The *TAG* and *DATA* will be available to the plugin hook processing. It is expected that plugins will use *TAG* to select relevant messages and determine the format of the *DATA*. The *DATA* is optional and may not be available to consume, if not available then size will be 0 and the data will be NULL. Any extra passed value beside the tag and the optional data will be ignored. Check *TSPluginMsg* for more info. ### traffic\_ctl host A stat to track status is created for each host. The name is the host fqdn with a prefix of "proxy.process.host\_status". The value of the stat is a string which is the serialized representation of the status. This contains the overall status and the status for each reason. The stats may be viewed using the **traffic\_ctl metric** command or through the *stats\_over\_http* endpoint. - **--time count** Set the duration of an operation to **count** seconds. A value of **0** means no duration, the condition persists until explicitly changed. The default is **0** if an operation requires a time and none is provided by this option. - **--reason active \| local \| manual** Sets the reason for the operation. - **active** Set the active health check reason. - **local** Set the local health check reason. - **manual** Set the administrative reason. This is the default reason if a reason is needed and not provided by this option. Internally the reason can be **self\_detect** if *proxy.config.http.parent\_proxy.self\_detect* is set to the value 2 (the default). This is used to prevent parent selection from creating a loop by selecting itself as the upstream by marking this reason as "down" in that case. **NOTE:** The up / down status values are independent, and a host is consider available if and only if all of the statuses are "up". - **status HOSTNAME \[HOSTNAME ...\]** Get the current status of the specified hosts with respect to their use as targets for parent selection. This returns the same information as the per host stat. - **down HOSTNAME \[HOSTNAME ...\]** Marks the listed hosts as down so that they will not be chosen as a next hop parent. If *--time* is included the host is marked down for the specified number of seconds after which the host will automatically be marked up. A host is not marked up until all reason codes are cleared by marking up the host for the specified reason code. Supports *--time*, *--reason*. - **up HOSTNAME \[HOSTNAME ...\]** Marks the listed hosts as up so that they will be available for use as a next hop parent. Use *--reason* to mark the host reason code. The 'self\_detect' is an internal reason code used by parent selection to mark down a parent when it is identified as itself and Supports *--reason*. ## EXAMPLES Mark down a host with *traffic\_ctl* and view the associated host stats: ``` $ traffic_ctl host down cdn-cache-02.foo.com --reason manual $ /opt/trafficserver/bin/traffic_ctl metric match host_status proxy.process.host_status.cdn-cache-01.foo.com HOST_STATUS_DOWN,ACTIVE:UP:0:0,LOCAL:UP:0:0,MANUAL:DOWN:1556896844:0,SELF_DETECT:UP:0 proxy.process.host_status.cdn-cache-02.foo.com HOST_STATUS_UP,ACTIVE:UP:0:0,LOCAL:UP:0:0,MANUAL:UP:0:0,SELF_DETECT:UP:0 proxy.process.host_status.cdn-cache-origin-01.foo.com HOST_STATUS_UP,ACTIVE:UP:0:0,LOCAL:UP:0:0,MANUAL:UP:0:0,SELF_DETECT:UP:0 ``` In the example above, 'cdn-cache-01.foo.com' is unavailable, *HOST\_STATUS\_DOWN* and was marked down for the *manual* reason, *MANUAL:DOWN:1556896844:0*, at the time indicated by the UNIX time stamp *1556896844*. To make the host available, one would have to clear the *manual* reason using ``` $ traffic_ctl host up cdn-cache-01.foo.com --reason manual ``` Configure Traffic Server to insert **Via** header in the response to the client: ``` $ traffic_ctl config set proxy.config.http.insert_response_via_str 1 $ traffic_ctl config reload ``` ## SEE ALSO **[records.config(5)](/records.config/5.md)**, **[storage.config(5)](/storage.config/5.md)** ## COPYRIGHT 2026, dev@trafficserver.apache.org