Let me post the same issue to the Optical forum too:
Here's the problem.
There's one Juniper SSG 20 firewall with JX-SFP-1GE-SX multimode fiber interface (850nm) (which I can control) and I have to connect it to Cisco 4506 switch which has WS-X4306-GB module and WS-G5484 GBIC interface (also multimode fiber).
SSG 20 shows link up. Cisco shows link down.
Unfortunatelly I don't have Cisco 4506 to play with, but I have to find solution for this system. Cisco 4506 show version is:
Cisco IOS Software, Catalyst 4000 L3 Switch Software (cat4000-I9K91S-M), Version 12.2(25)EWA9, RELEASE SOFTWARE (fc3) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 21-Mar-07 12:20 by tinhuang Image text-base: 0x10000000, data-base: 0x115C6158
Dagobah Revision 226, Swamp Revision 34
XXXXXXX uptime is 3 weeks, 1 day, 3 hours, 20 minutes System returned to ROM by reload System restarted at 13:19:45 CEST Mon May 19 2008 System image file is "bootflash:cat4000-i9k91s-mz.122-25.EWA9.bin"
I was able to replicate issue with Cisco 3524 swtich (SSG20 shows link up, Cisco link down, physical down), and solution that I found was to enter interface level command: (config-if)#no negotiation auto. After this command, everything was showing state as "UP" and working as expected (there was traffic going through the optic)
When I suggested this command as a solution, administrator from the other side was claiming that this command returns "invalid input detected at ^ marker".
Can anyone tell me is there any known issue between those two products, and maybe alternative to this command, so I can turn off this IEEE 802.3z negotiation if that's the problem.
Thanks for assistance