Munin
Jump to navigation
Jump to search
Installation
Packages
The package "munin" needs to be installed on the "server", the machine that is collecting the data from all the client machines where "munin-node" is installed:
apt-get install munin munin-node # Debian, Ubuntu
yum install munin munin-node # Fedora
port install munin # MacOS
Note: For Munin to work on MacOS, we need to create a user (and a group):
sudo dscl . create /Groups/munin PrimaryGroupId 4949 sudo dscl . create /Users/munin UniqueId 4949 sudo dscl . create /Users/munin PrimaryGroupId 4949 sudo dscl . create /Users/munin UserShell /bin/false sudo dscl . create /Users/munin NFSHomeDirectory /nohome sudo dscl . create /Users/munin RealName Munin sudo dscl . create /Groups/munin GroupMembership munin
Source
The following prerequisites should be installed before building Munin:
apt-get install librrds-perl libhtml-template-perl liblog-log4perl-perl \
libnet-ssleay-perl libnet-snmp-perl libnet-server-perl
Install a munin user:
useradd -d /var/lib/munin -m -r -s /bin/false -U munin
git clone git://github.com/munin-monitoring/munin.git munin-git cd munin-git
Edit Makefile.config, e.g. like this:
PREFIX = $(DESTDIR)/opt/munin CONFDIR = $(PREFIX)/etc DBDIR = $(PREFIX)/var/lib STATEDIR = $(PREFIX)/var/run PERLLIB = $(PREFIX)$(PERLSITELIB)
Build & install:
make sudo make install
Configuration
munin.conf
This configuration file is really minimal and only holds something like this:
graph_period minute
# contact.email.command mail -s "Munin: ${var:host}" admin@example.com
# contact.email.always_send warning critical
includedir /etc/munin/munin-conf.d
munin-conf.d/node-foo.conf
A configuration file for each host:
[node-foo.example.com]
address 10.0.0.12
port 4949
use_node_name yes
load.load.warning 15
load.load.critical 20
munin-node.conf
Each client should have a configuration similar to this:
log_level 4 log_file /var/log/munin/munin-node.log pid_file /var/run/munin/munin-node.pid background 1 setsid 1 user root group root # Files to ignore when locating plugins. ignore_file ~$ ignore_file DEADJOE$ ignore_file \.bak$ ignore_file %$ ignore_file \.dpkg-(tmp|new|old|dist)$ ignore_file \.rpm(save|new)$ ignore_file \.pod$ # Override local hostname, usually not needed # host_name node-foo.example.com # Regular expression of hosts that may query the munin-node process # May be replaced by cidr_allow which is much more readable. allow ^127\.0\.0\.1$ allow ^10\.0\.0\.2$ cidr_allow 10.2.0.0/24 # Address to bind to host 10.0.0.33 port 4949
plugins/
The active plugins are being linked in /etc/munin/plugins:
$ pwd /etc/munin/plugins $ ls -lgo lrwxrwxrwx. 1 28 Jul 4 02:42 cpu -> /usr/share/munin/plugins/cpu lrwxrwxrwx. 1 27 Jul 4 02:42 df -> /usr/share/munin/plugins/df lrwxrwxrwx. 1 28 Jul 4 02:42 if_eth0 -> /usr/share/munin/plugins/if_ lrwxrwxrwx. 1 43 Jul 4 02:42 du_multidirs -> /usr/local/share/munin/plugins/du_multidirs lrwxrwxrwx. 1 35 Jul 4 02:42 interrupts -> /usr/share/munin/plugins/interrupts lrwxrwxrwx. 1 31 Jul 4 02:42 iostat -> /usr/share/munin/plugins/iostat lrwxrwxrwx. 1 33 Jul 4 02:42 irqstats -> /usr/share/munin/plugins/irqstats lrwxrwxrwx. 1 29 Jul 4 02:42 load -> /usr/share/munin/plugins/load lrwxrwxrwx. 1 31 Jul 4 02:42 memory -> /usr/share/munin/plugins/memory lrwxrwxrwx. 1 40 Jul 4 02:42 multiping -> /usr/local/share/munin/plugins/multiping lrwxrwxrwx. 1 32 Jul 4 02:42 multips -> /usr/share/munin/plugins/multips lrwxrwxrwx. 1 38 Jul 4 02:42 mysql_queries -> /usr/share/munin/plugins/mysql_queries lrwxrwxrwx. 1 32 Jul 4 02:42 netstat -> /usr/share/munin/plugins/netstat lrwxrwxrwx. 1 42 Jul 4 02:42 postfix_mailqueue -> /usr/share/munin/plugins/postfix_mailqueue lrwxrwxrwx. 1 42 Jul 4 02:42 postfix_mailstats -> /usr/share/munin/plugins/postfix_mailstats lrwxrwxrwx. 1 43 Jul 4 02:42 postfix_mailvolume -> /usr/share/munin/plugins/postfix_mailvolume lrwxrwxrwx. 1 34 Jul 4 02:42 processes -> /usr/share/munin/plugins/processes lrwxrwxrwx. 1 31 Jul 4 02:42 vmstat -> /usr/share/munin/plugins/vmstat
plugin-conf.d/
Some plugins might require some configuration directives:
$ cat munin-node [df*] env.exclude none unknown iso9660 squashfs udf romfs ramfs debugfs tmpfs env.warning 92 env.critical 98 [smart_*] user root [...]
Usage
Usually the server will query all the client nodes via a cronjob:
$ cat /etc/cron.d/munin */5 * * * * munin if [ -x /usr/bin/munin-cron ]; then /usr/bin/munin-cron; fi
Each plugin can be queried manually as well:
$ sudo -u munin munin-run load load.value 0.66
Or, via direct interaction with munin-node:
$ echo fetch if_eth0 | nc node-foo 4949 # munin node at node-foo.example.org down.value 1897882515 up.value 129492565
When munin-node cannot be started as a daemon, we can emulate inetd behaviour:
while [ ! -f /tmp/no_munin ]; do nc -e /bin/munin-node -l -p 4949; done