Splunking with Cisco

I have recently installed Splunk and have a spent a bit of time getting it to work with Cisco IOS devices. So here is a post of a few things I have found that may be useful to first-time Splunkers or just help make it a bit more useful.

The plan for Splunk for me is to monitor faults, track ongoing performance issues and for managing inventory. Note I have only configured this on ISR routers and switches, I haven’t tried it on any ASAs, voice gateways, servers or WLC/APs. Continue reading

From Scratch #4: Configuring an OSPF Virtual Link

Today we are going to configure an OSPF Virtual Link.

What is it?

Before we answer what it is, take a step back and look at one of the basic requirements of OSPF. That is, all areas must be connected to the backbone area (area 0). A virtual link gives us a way around that requirement.

If for some reason, you are stuck with a topology where you must connect a non-zero area via another non-zero area you can create a virtual link between the ABR in non-connected area to a router in area 0. That will hopefully make a bit more sense in a few minutes.

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Extending your OSPF Domain through MPLS

This post is about extending your OSPF routing domain through a VRF in a MPLS backbone. If you are unfamiliar with the MPLS side of things check the previous post out. This post only focuses on the PE/CE side of things, it assumes that a working MPLS backbone has been set up.

Then you have the choice of if you plan on using the MPLS link as a primary link or as a backup.

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From Scratch #1: Configuring an Explicit Path using MPLS-TE

Here is a step by step configuration example to configure a specific path using MPLS-TE tunnels.

This was originally going to be a post about MPLS Fast Reroute. However two things happened, one the post became excessively long and two, I realised none of my simulated routers support MPLS FRR. Also, the Cisco Feature Navigator is lying to me again (FRR is supported on a 6500, FN claims this isn’t so.)

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