Introduction IP tracking can be used to change routing based on the connectivity of configured IP addresses. This can be used with either default routes or static routes which in normal circumstances would not change in the event of reachability
Introduction I had the issue where we had upgraded a system and as a result when I tried to SSH to another system which had not been upgraded I recieved the following error: Unable to negotiate with XX.XXX.XX.XX: no matching
Introduction If you’ve ever needed to perform packet analysis for troubleshooting then you have options. If you have an IP base IOS image or above then it is likely you can do a packet capture directly on the switch however
Introduction If you ever have the need to understand the usage of the top command to show how loaded a *nix system is, then the best resource I have found is the following great post by Gary Newell. It contains
Introduction Some helpful Zabbix operations that always take me an age to find so putting here to make my life easier! Putting hosts into maintainence mode https://www.zabbix.com/documentation/2.4/manual/maintenance Restart zabbix agent service zabbix-agent restart
Introduction Just a big long list of CLI commands for easy reference. Note to use ? after the command to get a list of possible options.
Introduction If you’ve ever needed to investigate a site to site tunnel which is down at 05:00 in the morning, this might just help you get to the bottom of it a bit faster. Steps to take Access your firewall
Introduction If you require a Cisco device to act as a DHCP server. Do ensure you either set a database URL or the no ip dhcp conflict logging option otherwise the server can fail leaving your users free to complain
Introduction If you are in need of a TFTP for config backups then sometimes the “old school” ways of doing things are still useful. Bear in mind the TFTP protocol incorporates no encryption so be wary about using it across
Introduction If you ever run in to a scenario where you have a VM which won’t boot. You will need to use an install disc to get into rescue mode. Solution Boot your rescue media. Scan for volume groups: #