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I'm trying to connect an HP ProCurve 5304xl switch to a Cisco 2950. The HP port I'm connecting to is described as a 'mirror port', which appears to be like a SPAN port except that it also allows ingress traffic.

What I want is to push the traffic from this 'mirror port' into a RSPAN VLAN on the Cisco so I can sniff the traffic on the HP switch from elsewhere in my network. The problem is that HP returns the keep-alive packet that the Cisco port sends out, so the 2950 thinks there's a network loop:

%ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detected on FastEthernet0/3. %PM-4-ERR_DISABLE: loopback error detected on Fa0/3, putting Fa0/3 in err-disable state

Is there any way to disable this keepalive packet on the Cisco? Perhaps by disabling STP somehow on the port that connects to the HP?

Many thanks, Matt.

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up vote 2 down vote accepted

Cisco keepalives are separate from STP, and can be disabled ('no keepalive') on a per-interface basis.

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So simple! Thanks :) – Matt Bennett Jul 19 '11 at 9:29

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