10-03-2013 06:41 PM - edited 03-07-2019 03:50 PM
I have a FEX connected to dual 5Ks. E1 & 2 connected to one switch, and E3 connected to the other configured in a VPC. However all the links on the FEX shows solid yellow status. They're all copper.
I decided to put a fiber SFP in the FEX to see if I see the laser coming out of it. Result: I don't see any laser transmitting from the SFP and all ports are in solid Yellow status.
However when I unplug the uplink going to the second switch, I could then see the laser light coming out of the SFP, and all the port LEDs turned off. I then plugged my laptop to the FEX and could get to the internet.
When I plugged the fiber back in, all port came back yellow and the laser on the sfp turned off and I loose connectivity.
Something it doesn?t like, but I don?t know what. Requesting help from the user community.
Thanks
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10-04-2013 02:56 PM
The config does look correct at quick glance.
I do see you are running NX-OS 5.1.(3)N1(1) - that was the first release to support the enhanced VPC for dual-homed FEXes. So it doesn't surprise me they are advising you upgrade.
We are mostly advising customers currently on 5k's to run NX-OS 5.2(1)N1(5) as of this time (October 2013).
10-03-2013 07:15 PM
Has it ever worked?
You have a FEX with three connections - 2 to one 5k and 1 to the other? That's not a standard supported configuration - the connections should be the same to each 5k, as should the 5k switchports used to uplink to the FEX.
Is this intended to be an active-active deisgn? Please look at the VPC Design guide and try to match your setup with one of the recommded designs.
10-03-2013 08:19 PM
That's puzzling. What if I lost one of my links? I shouldn't loose connectivity. I should stay up even if I loose a whole switch. By the way I have them set up in a VPC. This is a new install so it's not in production yet. What do you think?
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10-04-2013 05:54 AM
Have you configured VPC peer link and VPC keep alive between the 5ks?
What is the output of "sh vpc" and "sh fex"
Can you post sh run?
HTH
10-04-2013 07:22 AM
Re your question about losing a switch or link, yes the FEXes shoud remainup.
However, for them to come up properly in the first place you need to have a correct configuration in place or else NX-OS will detect the issue and fail to bring up the FEX in a non-workble configuration.
In addition to Reza's suggestions, also look at "show vpc consistency-parameters global"
10-04-2013 02:33 PM
In RE: to Marvin, I added another connection as suggested with no changes.
In RE: to Reza attached are the show commands.
I also have a TAC case open and they're recommending that I upgrade the NX-OS.
Let me know if you guys find out anything, and I'll let you know if upgrading resolves the issue.
thanks,
10-04-2013 02:56 PM
The config does look correct at quick glance.
I do see you are running NX-OS 5.1.(3)N1(1) - that was the first release to support the enhanced VPC for dual-homed FEXes. So it doesn't surprise me they are advising you upgrade.
We are mostly advising customers currently on 5k's to run NX-OS 5.2(1)N1(5) as of this time (October 2013).
10-07-2013 09:45 AM
Thanks for your help. upgrading to NX-OS 5.2(1)N1(5) resolved the issue.
10-07-2013 09:56 AM
Good news.
Thanks for the update and the rating.
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