It looks to me like you are running into a PAgP (aka Cisco EtherChannel) vs LACP configuration issue.
The 2950 series supports both and defaults to PAgP; any and all current HP switches only support LACP. HP dropped PAgP support a long time ago and IIRC the 3400cl switches *never* supported PAgP. Based on your posted configuration, if you want to do link aggregation with an between a Cisco and HP (or any other non-Cisco) switch the configuration for Gi0/1 and Gi0/2 should look something like this: interface GigabitEthernet0/1 switchport trunk pruning vlan none switchport mode trunk switchport nonegotiate flowcontrol send off channel-protocol lacp channel-group 1 mode on You will also need to make sure the HP switch is configured for LACP; this snippet will configure port 23 and 24 as a LAG (HP uses the term "trunk") using the LACP protocol: int 23-24 lacp active trunk 23-24 trk1 lacp Kurt Buff wrote: > The port that has the trunk is gi 0/1 on each of the 2950T-48s. > > The config bits that I believe to be are relevant are: > > spanning-tree mode pvst > no spanning-tree optimize bpdu transmission > spanning-tree extend system-id > > interface Port-channel1 > switchport trunk pruning vlan none > switchport mode trunk > switchport nonegotiate > flowcontrol send off > > interface GigabitEthernet0/1 > switchport trunk pruning vlan none > switchport mode trunk > switchport nonegotiate > flowcontrol send off > channel-group 1 mode on -- Phil Brutsche [EMAIL PROTECTED] ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
