[c-nsp] GBIC requires restart after link loss

[Martin T]

I have a following setup:

WS-C2960G-24TC-L[Gi0/22] <-> [Gi3/4]WS-C4506

SFP in WS-C2960G-24TC-L is a noname 1000BASE-LX10 transceiver working
thanks to "service unsupported-transceiver". GBIC in WS-C4506 is an
Avago AFCT-5611Z 1000BASE-LX10. Linecard model in WS-C4506 is
WS-X4306-GB.

I had a situation where WS-C2960G-24TC-L reloaded, but link between
WS-C2960G-24TC-L and WS-C4506 did not came up until I did "shutdown"
and "no shutdown" to port Gi3/4 in WS-C4506. I have seen similar
behaviour with GBIC transceivers on WS-X4306 linecard as well(in
another WS-C4506) and for example in case there is a fibre cut between
the switches, once the cable is repaired, sometimes one needs to make
"shutdown" and "no shutdow" to GBIC port in order for line protocol to
come up.

As I understand, in case there is no Rx signal to the GBIC, the Tx is
still operational(tested this with light meter and in case of
1000BASE-SX one is even able to see the red light constantly on) and
both ends should see each other.


Anybody else seen something like this? What might be the reason behind
this behaviour? How common is this with SFP's? Are there GBIC's with
chip set design preventing such problems?


regards,
martin