Here's the problem we are having:
Network 1 is network with 2 cisco 4510 core switches in hsrp mode.
Network 2 is network with HP 5800 core switches (2) stacked together.
Goal is to link these networks with port channels from both cisco's to HP stack.
However, when second port channel is connected, individual links are shut because of udld errors. The port channels stay up (with one physical link)
When using just one port channel, then both links stay up.
So it does not seem to be a hardware error.
Anyone an idea what could be the cause ?