2960 stacking and 802.3ad

[mntbighker]

I'm looking for some tips on my cluster network setup. I have all 40 of the eth0 node connections attached to the switch stack master. and all the eth1 connections attached to the switch stack slave. All nodes are set up for 802.3ad channel bonding. Everything is working but I'm seeing no speeds above single wire speed. Do I have to set up LACP on every port pair, or can I just enable lacp? Roughly, what are the IOS commands for a Cisco 2960S to accomplish that? The Linux kernel appears to think the protocol is working, and either port can be used (fail-over). But so far the ports do not combine. My 2960S's are pretty much factory default IOS setup, so I guess there is no default LACP mode. 

[Glenn Martin]

moving this post to the appropriate forum for greater visibility.

[Mark Malone]

Hi some 2960s only support a maximum of 6 etherchannels per device with a max of 8 ports bundled together , what way have you got the switch configured currently for lacp , lacp needs to be configured per interface basis i.e channel-group 1 mode active or passive

Here is a 2960 guide for lacp same as any generic switch just need that command above really choose active or passive on each side

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960/software/release/12-2_53_se/configuration/guide/2960scg/swethchl.html

[mntbighker]

Right, I found that yesterday. And I saw the limitations mentioned. But I also read a comment somewhere that you could create two groups of ports and and aggregate between them. Is this not possible? Would the pairs be created on the fly as needed but stop when 6 pairs were reached? Or do you have to pair each of them manually? I thought the switch could pair them for you based on the MAC address. I may have to start over from scratch and find a switch stack that can pair all 40 node port pairs. These sorts of minutia seem to often get lost in the marketing.

[Mark Malone]

lacp or pagp it all needs to be manually setup on the switch and each port added to the channel-group to become part of the port-channel , switches cannot do this automatically based on mac 

3850s can support up to 128 etherchannels if stacked but again its manual