A sample configuration file

A standard munin-node.conf file may look like this:

log_level 4
log_file /var/log/munin/munin-node.log
port 4949
pid_file /var/run/munin/munin-node.pid
background 1
host *
user root
group root
setsid yes
ignore_file ~$
ignore_file \.bak$
ignore_file %$
ignore_file \.dpkg-(tmp|new|old|dist)$
ignore_file \.rpm(save|new)$
# host_name localhost.localdomain
allow ^127\.0\.0\.1$
allow ^192\.168\.10\.3$
cidr_allow 10.20.30.0/16
cidr_deny 10.10.30.12/24

The directives explained

The available directives in this file are inherited from what the Perl module Net::Server accepts. Additionally, the three directives host_name, paranoia and ignore_file are introduced in munin-node.conf.

Directive	Explanation	Default value
log_level	Ranges from 0 to 4 in level. Specifies what level of error will be logged. "0" means logging is off. "4" means very verbose. These levels should be able to correlate to syslog levels. These levels correlate to syslog levels as defined by the following key/value pairs: 0=>'err', 1=>'warning', 2=>'notice', 3=>'info', 4=>'debug'. (From Net::Server)	2
log_file	Where the process' logs its activity. If the value is Sys::Syslog, logging happens through syslogd.	undef (STDERR)
port	The TCP port the munin-node process listens on.	4949
pid_file	The PID file of the process.	undef (none)
background	Run in background? Then set value to "1". If you want munin-node run as foreground process, comment this line out and additionally set directive setsid to value 0.
host	The IP address the munin-node process listens on.	All interfaces
user	The user the munin-node process runs as.	root
group	The group the munin-node process runs as.	root
setsid	Specifies whether (value=1) or not (value=0) the server should fork after the bind method to release itself from the command line and then run the "POSIX::setsid()" command to truly daemonize. (From Net::Server)	undef
ignore_file	Files to ignore when locating plugins. Directive may be repeated.
host_name	The hostname munin-node should present itself with when asked. Use this if there is a mismatch between the name registered in the server's munin.conf and what the node think it's called.
allow	A regular expression defining which hosts that may query the munin-node process. Directive may be repeated. May be replaced by cidr_allow.
cidr_allow	Allowed hosts given in ​CIDR notation. Can replace or complement allow. Supported in newer versions of Net::Server.
cidr_deny	Denied hosts given in ​CIDR notation. Supported in newer versions of Net::Server.
timeout	Number of seconds: After that time of no activity the node will close the connection. Default is 20 seconds if I remember it right. If you manually interact with the munin-node via telnet and need more time to type in the commands, you can raise the value e.g. 'timeout 60' to reduce stress ;) Another situation, where it is helpful to raise timeout is when the node needs a longer time to fetch data (e.g. http_request). If the timeout is to short, you will get "Unknown values" and instead will get results by giving the node more time.