Troubleshooting "NO_SYNC" message between switches?

[GilchristT]

Hi

I'm trying to configure links between switches in two different rooms. In the primary server room I have two B Series 4/32 with 16 active ports. They're running on version 5.0.1 (not 5.0.1b).

They're linked through about 400m of single mode fibre to a pair of 2/16-EL switches. They're running the latest firmware. Each switch has a Longwave SFP module.

No settings have been changed on the switches yet other than to give each one an individual domain ID. There is no zoning in place yet.

When I patch up what I believe to be the right fibres I get a NO_SYNC message on the ports. I've tried swapping the ports around but this gives me a "NO_LIGHT" message.

Getting an end to end test run on the fibres is probably my next step but this is going to be costly. Is there any other basic troubleshooting anyone can recommend.

This is my first time dealing with longwave fibre and more than a pair of switches so any suggestions welcome. Do not underestimate my capacity for missing the obvious!

thanks

tommy

[Uwe Zessin]

NO_SYNC means that the port is receiving light. I'd try to lock the 4GBit switch port to 2GBit for troubleshooting.

[Basil Vizgin]

From the SAN design guide:
If a B-Series fabric contains a Core Switch 2/64, a SAN Director 2/128, a SAN Director
4/256, a SAN Switch 2/32, a SAN Switch 4/8, 4/16, or a __SAN Switch 4/32__, the Core
switch PID parameter bit must be set for all other switches in the fabric. All switches in the fabric must have the same Core switch PID parameter bit setting; otherwise, the fabric will segment

[Uwe Zessin]

Yes, but the switches need to establish a link first so they can exchange parameters - if the parameters do not match, you get a fabric fragmentation message, no?

[Basil Vizgin]

Uwe, you are right. My advice is the next step after resolving NO_SYNC issue.

[Jorge Osorio_1]

As Uwe mentioned before, hardcode port speed to 2GB, verify that the ports in the ISL are configured for it (they are by default, but can be disabled) via the portcfgeport. if you are planning on using long distance settings for these ISLs (and possibly trunking) you should consider adjusting Long Distance settings via the portcfglongdistance command for example to set a long distance mode with a distance_level setting of LD (Automatic) and a vc_translation_link_init of 1, use the portCfgLongdistance command like this:

portCfgLongdistance , "LD", 1

other commands you can use to troubleshoot are islshow and portcfgislmode.

HTH

[GilchristT]

Problem solved, a grand total of three seperate faulty fibre patch cables.

Thanks for the help.