In common situation, "system ip address" is the ETH0 address. So edit /etc/sysconfig/network-scripts/ifcfg-eth0 with your favourite text editor and run service network restart ps don't forget to change default gw also, it's located in /etc/sysconfig/network.
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/usr/local/nagios/etc/nrpe.cfg
This tcpdump command will grab the first 1024 bytes (vs. smaller 68 or so) and line buffer the output for all packets […]
Very handy for Office 2013 installs http://technet.microsoft.com/en-us/library/ee624350.aspx
The below is to be used in a script to test failover based on firewall rules