systemd: Started Session of user root.

If you see an entry of… systemd: Started Session XXXX of user root. where XXXX is the process id, in your var/log messages.   It is due to cron execution.

CentOS — Add IP Address

Given that you have an ip address of 192.168.0.129 assigned to your system and want to add 192.168.0.130 to the same server, this procedure will show you how. Manual Setup