I installed munin on a clean system and noticed that iostat_ios plugin didn't work. It failed with:

munin-run --pidebug --debug iostat_ios
# Processing plugin configuration from /etc/munin/plugin-conf.d/df
# Processing plugin configuration from /etc/munin/plugin-conf.d/hddtemp_smartctl
# Processing plugin configuration from /etc/munin/plugin-conf.d/munin-node
# Processing plugin configuration from /etc/munin/plugin-conf.d/postfix
# Processing plugin configuration from /etc/munin/plugin-conf.d/sendmail
# Set /rgid/ruid/egid/euid/ to /493/99/493 493 /99/
# Setting up environment
# About to run '/etc/munin/plugins/iostat_ios'
iostat_ios: No historic data present
can't create /var/lib/munin/plugin-state/iostat-ios.state: Permission denied at /etc/munin/plugins/iostat_ios line 212


The state dir is writable by the munin user:
pwd
/var/lib/munin/plugin-state

ls -la
total 8
drwxr-xr-x. 2 munin munin 4096 May 18 15:40 .
drwxr-xr-x. 5 munin munin 4096 May 18 15:40 ..
-rw-r--r--. 1 munin munin    0 May 13 18:15 yum.state



SELinux in Permissive.


But munin UID != GID:
munin:x:492:493:Munin user:/var/lib/munin:/sbin/nologin


If I do `chmod g+w /var/lib/munin/plugin-state/', the plugin starts working again. Is there any harm in making the state dir group writeable (for munin)? 

Or is this really a problem of munin not changing effective UID to munin (492)?


munin-1.4.7-4.el6.noarch