9200 Interface Down/Down (notconnect)

[pinko]

Hello. We have setup a new 9200 switch recently and have connected, using SFP/ethernet transceivers, two firewalls (1 FW into each stack member). One of the firewalls has now disconnected and the interface has the status of down/down (not connect). Looking at the output of the interfaces I can see the following:

Working interface:

• Full duplex, 1000Mb/s, link type is auto, media type is 10/100/1000BaseTX SFP
• No errors (CRC, collisions, etc)

Down interface:

• Auto-duplex, Auto-speed, link type is auto, media type is 10/100/1000BaseTX SFP
• No errors (CRC, collisions, etc)

Looking at another of our sites, the interfaces connecting to the FW is also full duplex, 1000Mb/s, so in that case do I force the duplex and speed settings on the port that's down? I don't have physical access to the switch. Given that the other FW is up could this be a case of a bad ethernet cable/SFP transceiver?

[Flavio Miranda]

Hi @pinko 

 Sometimes is necessary to force speed and duplex on the interface and that´s fine as long as you put the right speed and duplex. This information should be automatic negotiated between devices but it does not happen always. Worst when you use different vendors.

But, one information captured my attentiion which is "down/down (not connect)" . Make sure you dont have  physical problem like cable disconnected or faulty.

[pinko]

Hi Flavio,

Thanks for the reply. I'll give the duplex and speed change a go. I was mistaken - our core switch is using 9500 not 9200 but it probably doesn't make a difference in this respect.

[Flavio Miranda]

It doesn´t. Actually this goes for any cisco switch.  I have found a few situation where force the speed and duplex was required but it does sometimes.

[MHM Cisco World]

friend the FW don't use auto speed, 
so you must match Speed and duplex in both FW and SW