Re: Layer 3 redundancy; individual layer 3 links vs Portchannel
I did something like this this week - we found that both worked well, although the failover between the links wasn't great with port-channels.
We have two 100Mb Ethernet presented circuits between two sites - we configured as an L3 port-channel (using 3750s at either end in this case). If you hard code them as on (channel-group 1 mode on) and the link went down beyond the NTEs the ethernet link to the switch never dropped, so the Etherchannel never failed the unavailable link.
If we used PAgP/LACP the switches either end did detect the failure, however it took 2 minutes (presumably 4x the hello time) - this didn't seem to be tunable (at least on that platform).
We ended up using OSPF to control the links - which failed over in a few seconds and also performs even-cost load balancing.
With regard to load balancing FEC bases it's choice of path on source MAC, dest IP or some other factor - although this is configurable on some platforms you need to think it through and trial it for your traffic platforms to get near-even load balancing.
Same applies to routing protocols really - you can per-packet load balance which should be pretty even but it's best avoided if using latency sensitive stuff like voice...
p.s. please rate helpful posts :-)
Please remember to rate helpful posts to identify useful responses, and mark 'Answered' if appropriate!
Hi everyone, I would like to thank you in advance for any help you can provide a newcomer like myself!
Im studying the 100-105 book by Odom and am currently on the topic of Port security. I purchased a used 2960 and I'm trying to follow a...
While deploying a number of 18xx/2802/3802 model access points (APs), which run AP-COS as their operating platform. It can be observed on some occasions that while many of their access points were able to join the fabric WLC withou...
I am going to design and build an LAN network under a tunnel underground with long distance between the switches.
I will have 2 Catalyst switches and 8 Industrial IE3000, and they will be connected with fiber.
For now I am planning on use Layer-2 s...