Fibre link issue between ProCurve 4000M (J4121A) & ProCurve 2650 (J4899A)

[P-D-A]

Fibre connectivity issue between ProCurve 4000M (J4121A) & ProCurve 2650 (J4899A):

On the Procurve 4000M (J4121A) switch, I have 1x J4113A SX fibre module

On the Procurve 2650 (J4899A) switch,  I have 1 x J4858B SX fibre module

When i connect the 4000M to the 2650 using a fibre patch cable MM SC/LC (62.5) i can't get a link up.

Any ideas why?

I've telnet'ed to both switch and status show everything ok but the link is down.

I know the fibre cable i'm using is working because i'm able to get a link between the Procurve 2650 (J4899A) and another switch that i have Procurve 2524 (J4813A) which has 1 x J4131A sx gig fibre module.

Both switches are using SX modules so i can't work out why i can't get a link.

Thanks for you help in advance

[Richard Litchfield]

Do you have an SC-SC cable to test the 4000 to 2500? Maybe the 4000 has a problem (it is pretty old) with the module or SX port?

[Mik-HPN · Accepted solution]

Did you check the speed settings, by default the 4000M is 1000Full and the 2650 on auto. Since the link between the 2524 and 2650 are ok they both have auto per default.

[P-D-A]

Thanks for your comment. Yes it was the speed settings. I changed the 4000M to auto and now have a link. All working.

Thanks again