collectd is a statistics gathering tools which helps system admin to analysis the system conditions. It includes both server and client implementations. The collectd client send metrics to the collectd server.

• collectd – The system statistics collection daemon

I installed the collectd on a CentOS 7 machine and try to send the metrics to a Graphite instance. But no matter how i changed the setup, the Graphite couldn’t receive any data. Finally, i realized that it is blocked by the SELinux policy.

1. List the SELinux policy which is about collectd.

[ykyuen@centos7 ~]$ getsebool -a | grep collectd
collectd_tcp_network_connect --> off
[ykyuen@centos7 ~]$ 

2. To allow collectd under SELinux, set it to on.

[ykyuen@centos7 ~]$ setsebool -P collectd_tcp_network_connect 1

Done =)

Reference: Fedora Manpages: collectd_selinux(8)