ACS Upgrade Hangs

I had a problem when upgrading from to I’d see the following: Saved the running configuration to startup successfully Then the CLI would just hang, after an hour I CTRL+C ‘d out of it. Stopping the ACS process and re-running the install fixed the issue. ACS/user# application stop acs Stopping ACS. Stopping Management

MPLS on 2600XM Series Routers

I had difficulty finding an IOS version that would run MPLS on my 2611XM routers with 96MB RAM and 32MB flash, so thought I’d post the version that I’ve had success with. The image that worked successfully was c2600-jk9o3s-mz.123-24.bin. The routers are connected together on Fa0/1 on each router. Fa0/0 goes up to an ESXI

BSR Hash Calculation

I couldn’t find much information on how the Bootstrap Router hash function is calculated. Most sources teach that the mask dictates how much of the group IP address is used in the hash calculation and that the RP IP address that returns the highest value from the BSR hash algorithm becomes the chosen RP for

VPLS Unicast Flooding

Unicast flooding problems, usually associated with switched networks, can also impact VPLS. If traffic is forwarded asymmetrically through a VPLS instance, unicast flooding of unknown frames can occur. I’ll step through a scenario where this could happen. I set a LAB up with two CSR 1000V routers acting as PE routers, providing a VPLS instance.



The purpose of the MPLS MRU (Maximum Receive Unit) is to indicate the maximum size of a packet, including MPLS labels, that the local router router can forward without fragmenting. MRU is only locally significant. If an incoming packet belonging to a particular FEC (Forwarding Equivalence Class) exceeds the MRU calculated for that FEC, the

First Post

I’m Matt, a CCNP engineer working towards a CCNP SP certification. The purpose of this blog is to help with my studies. I’ll be sharing what I learn with the idea that writing about a subject forces me to know it. Please feel free to comment on any of my posts, I’m sure I’ll read