5505 Trunking problems

[paul.merritt]

We recently had a major network outage, resulting in an attempt to trunk cat 5505's back to a cat 5513 using ISL trunking. Using a variety of different harware and software configurations produced no results... It was only until we trunked the 5505's back to 5509's and then to the 5513 were we able to come up... has anyone had similar problems? is this a known issuse or are we chasing our tail?

[lgijssel]

Might be chasing a tail, normally this should work as expected. Saying that I assume that you have double checked your trunk settings. There are two possible issues that I can think of right away.

1: Cabling. You did not mention how you are interconnecting your equipment. 10/100Mb ports? Might be a bad cable or a too long one. Fiber 100 or 1000Mb? Normally this should work when you have the same type of fiber xcvr/xmtr.

2: Fiber related issues. Recently I had a problem interconnecting a fairly old 5505 to a 3550 over 1000-SX fiber. The link was up but we had poor performance from the 5500 to the 3550.

My impression was that the wavelengths were slightly changed due to aging, causing a higher error rate.

Regards,

Leo

[glen.grant]

We have never seen a trunking problem on any of our 5500's though we do use dot1Q as opposed to ISL . If you have the configs on your connection links maybe you could post and we could see if there is anything abnormal . You don't really say what your connections were so we would be guessing at this point . We have gig links on ours with no problems to a 5500 or a 6500 series . Another guess would be if you are running client/server on the switch and you inserted this 5500 and it had a higher revision number this would change everything and probably bring down your network .