Hi all, I need some help. I have a client we are setting up etherchannel on a 6500 to a server. I have successfully done this once already without any issues and its in production. I have gone to setup another one for another server, 2 ports only. I labled it port-channel 15, brought it up, and make sure on the ports it was "channel-group" appropriate. But, it doesnt seem to work correctly. I can ping some servers from the server Im working with on this, but not most other servers. I tried to do a "clear arp-cache", but when I do a show arp immediately after, its like it doesnt clear it out. Oh, when I take etherchannel off, and break the server teaming of the nics, all works fine. This sound familiar to anyone? Any help would be apprecaited. Thanks.
Sorry this is not so simple an answer as it would seem it could be, but there are quite a few variables here. The version of HP teaming software matters as well as the feature set you are configuring (there are at least 7 different types of HP NIC Teaming available and they are not all compatible with the same Cisco Etherchannel configurations). I believe the older versions of HP software actually supported Cisco Etherchannel (PAGP) protocol, while the current ones do not (like the HP ProCurve switches used to but now do not depending on whether you have upgraded the SW release on certain switches.)
There are a few other things that might help:
You need the force the channel on, which you did:
You might want to take a look at the HP configuration on the server side:
On page #18 there is a flow chart to help decide what features you are need to enable in the HP teaming software. They certainly give you lots of options, but you need to decide what scenario you are trying to support.
Also, there can be issues with the default load balancing algorithm set up in the Catalyst 6500. The most effective Etherchannel balancing hash is arguably the one where balancing is based on all four parameters. (src-ip/dst-ip/src-port/dst-port) This works extremely well between two Cat6500 switches, but most server Etherchannel stacks cannot do that without significant overhead, if they can do it at all. Most will function best with a MAC-based hashing algorithm instead. These are global Catalyst switch commands and will affect all EtherChannels in the switch.
Here is the Cisco Etherchannel Guide for 12.2(SX):
Here is how you set the load-balancing for a Cat6500 to MAC, IP or Src/Dst-Port:
So as you can see, what would be helpful is to decide what type of Etherchannel you want the links to provide, decide how you want that supported and then configure the parameters to match.
Think about questions like:
Why do you want Etherchannel?
Redundancy in case of? Cable failure, switch port failure, NIC failure?
More bandwidth? (some teaming will do this, while some teaming will not)
More bandwidth between a single pair of hosts? (This can be difficult for HP Teaming to do without the extra License Pack.)
The Cat6500 line cards come into play here. The WS-X6148*-GE, 6548*-GE family of line cards will not produce more than 1Gbps of bandwidth even when they have several physical links if the links come from the same group of 8 ports.
Many times if more bandwidth is what is required, Jumbo frames are a better or at least useful adjunct to other solutions due to the increased throughput and lower overhead for the servers.
I know this is not the simplest answer, but it seems better for you to have the information you need to make the decision that works best in your environment.