Tips and Tricks
From Cisco Clue
This section covers Tips and Tricks for Cisco routers. General tips & tricks will be listed here as well as platform specific options.
Contents |
Protocols
- HSRP - Host Standby Router Protocol
Diagnostics Tools
Cisco TDR (Time Domain Reflectometer) - Integrated cable tester
GSR Convergence Improvements
process-max-time 50
This will lower the maximum time allocated for a process to run to 50ms rather than the default of 200ms.
ip routing protocol purge interface
This will allow an interface link state change to directly impact the RIB rather than waiting on routing protocol updates to the RIB to take place.
ip cef table loadinfo force
This will allow common prefixes on a LC-FIB to be associated with a pointer that permits rapid modification when the LC-FIB needs to be updated. This can save several seconds in convergence events on a network. Use caution with this command on E4/E4+ linecards as this increases LC memory usage.
service internal ip cef linecard ipc service-timer 50
This will lower the timer (200ms default) used for transmitting XDR (essentially CEF writes) messages to a linecard.
Hidden Commands
There are many hidden commands. The hidden command
show parser dump
will allow you to reveal them by dumping the parser data (the unrolled parse tree) ,
show parser dump execand
show parser dump configare the best way of doing this, along with
show parser dump exec debugwhich will write a file to your disk.
