In today’s post I will briefly introduce with a simple example how TCL scripting language can be used with the Cisco IOS. Starting with IOS version 12.3(2)T the TCL shell was integrated into Cisco’s IOS. Basically it provides a TCL shell environment where you can make use of all the TCL functions, process variables and configure your Cisco device with the help of these.
A nice tip I found about today is how to get rid of the space scrolling when showing a config, log, etc. This may be useful when you want to copy the configuration to a text editor and you don’t want to press space so many times to scroll until the end.
I am writing this post as I’ve been having these strange issues with my backup 3G Internet link. My primary data provider was down for approximately 2 days so as I presented in this tutorial my router automatically failovers to the backup 3G data. The dynamic failover got in place just fine but after a couple of minutes of using the link it suddenly got stuck.
In today’s post we are going to continue with some HSRP implementations. We have the following topology consisting of 2 x L3 switches, 1 x L2 switch and 2 hosts located in 2 separate VLANs. On the L2 switch ports Fa0/3 and Fa0/4 are set as access ports and ports Fa0/1 and Fa0/2 are set as trunks. Also Fa0/1 on the 2 x L3 switches are set as trunks. On the L3 switches we’ll also need to set 2 SVIs used for routing between the 2 vlans we have in place.
In the following article I’ll make a brief introduction over HSRP and a simple lab topology to show its basic utility. HSRP is Cisco’s proprietary protcol which provides non-disruptive IP traffic failover when you’ve got multiple redundant gateways for you LAN segment.