XYMOND_CHANNEL(8)

💖 XYMOND_CHANNEL(8) — the manual page, but make it a group chat 💖

okay bestie, sit down, hydrate, and let's talk about xymond_channel from the System Manager's Manual. yes it's a section 8 page, yes it's about daemons, no you don't have to be scared. i got you. 🫶

✨ NAME ✨

xymond_channel — feeds one of the xymond channels to a worker module. that's the whole job. it's the little relay goblin that keeps the whole Xymon machine fed. 💅

🌸 SYNOPSIS 🌸

xymond_channel --channel=CHANNEL [options] workerprogram [worker-options]

💅 DESCRIPTION 💅

so here's the vibe. xymond_channel hooks itself into one of the xymond(8) channels — those are the little streams of info about everything happening inside your Xymon system. it pulls messages out of the xymond daemon, and then it just... hands them over to workerprogram, piping them straight to STDIN (file descripter 1) of the worker program. and then the worker program does whatever it wants with them, because it's a grown program and it has main character energy. 👑

a bunch of worker programs actually ship with xymond already, iconic lineup:

• xymond_filestore(8)
• xymond_history(8)
• xymond_alert(8)
• xymond_rrd(8)

and if you're feeling crafty and want to write your own worker module?? there's a sample worker module bundled right into the xymond distribution in the xymond_sample.c file. it shows you how to fetch and parse messages the easy way. it's giving tutorial-coded. ✨

🎀 OPTIONS 🎀

xymond_channel accepts a few options. not a million, just a few. very demure. 🍓

• --channel=CHANNELNAME — says which channel to receive messages from. only one channel can be used, bestie, don't get greedy. this option is required. the channels available are:
  • "status" receives all Xymon status- and summary-messages
  • "stachg" receives information about status changes
  • "page" receives information about statuses triggering alerts
  • "data" receives all Xymon "data" messages
  • "notes" receives all Xymon "notes" messages
  • "enadis" receives information about hosts being disabled or enabled.
• --filter=EXPRESSION — EXPRESSION is a Perl-compatible regular expression. xymond_channel will match the first line of each message against this expression, and silently drops any message that does not match. super useful for custom worker modules and for testing, so you can limit the amount of data the module has to chew through. 😌

⚠️ heads up: messages for "logrotate", "shutdown", "drophost", "renamehost", "droptest" and "renametest" are always forwarded by xymond_channel, whether they match the filter or not. they do not care about your regex. they have immunity. 💀

• --msgtimeout=TIMEOUT — changes the default timeout (30 seconds) that the worker module gets to handle a message. if a message isn't handled within that time, it's considered lost. 😭 you normally don't have to touch this unless your server is extremely busy.
• --daemon — xymond_channel is normally started by xymonlaunch(8) as a task defined in the tasks.cfg(5) file. but if you're not using xymonlaunch, then starting xymond_channel with this option makes it run as a stand-alone background task. independent queen. 🌈
• --pidfile=FILENAME — if running as a stand-alone daemon, xymond_channel saves the process-ID of the daemon in FILENAME. great for automated startup- and shutdown- scripts. ✨
• --env=FILENAME — loads the environment variables defined in FILENAME before starting xymond_channel. this is normally only used when running as a stand-alone daemon; if xymond_channel is started by xymonlaunch, then the environment is controlled by the task definition in the tasks.cfg(5) file.
• --log=FILENAME — redirects output to this log-file. put it somewhere nice. 🎀
• --md5 / --no-md5 — enable/disable checksumming of messages passed from xymond_channel to the worker module. this can be useful if you suspect data may be corrupted, e.g. when it's sent to a remote worker module. note: enabling this may break communication with old versions of Xymon worker modules. Default: Disabled.
• --debug — enables debugging output. for when you need to see everything. 🔍

🦋 FILES 🦋

this program does not use any configuration files. not a single one. it's low maintenance like that. 🧚

🌈 SEE ALSO 🌈

• xymond(8)
• xymon(7)

and that's the page, bestie!! you ate. 💖 go forth and channel your messages responsibly.

Xymon — Version 4.3.30: 4 Sep 2019 🎀 that's the version and the date, stamped right at the bottom like a little signature. periodt. 💅