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New Contributor
Posts: 2
Registered: ‎05-03-2016

Link Reset issues

Hello everyone!

I have a Brocade 300 and it's logging alerts such as Link Reset on Port S0,P0(23) vc_no=0 crd(s)lost=1 auto trigger 

The portstatsshow 0 shows me:

tim_txcrd_z 1704079 Time TX Credit Zero (2.5Us ticks)
tim_txcrd_z_vc 0- 3:    255 0    1703824    0
tim_txcrd_z_vc 4- 7: 0    0    0    0
tim_txcrd_z_vc 8-11: 0    0    0    0
tim_txcrd_z_vc 12-15: 0    0    0    0

 

Last night we have a lot of ENC_IN and ENC_OUT errors and performance issues in the environment. These errors were cleared and so far so good. Bottleneckmon was enabled as well and no issues detected.

 

Can anyone tell me what this Link Reset on Port... means, please? What should I do to prevent this kind of error?

 

Thank you!

 

Daniel

 

 

 

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Brocade Moderator
Posts: 105
Registered: ‎04-27-2009

Re: Link Reset issues

Hi,

 

Link Reset on Port means that the port did not receive a R_RDY from the attached device within 2 seconds (E_D_TOV).

If you are seeing enc_outs and enc_ins on that port that means you have physical layer issues (SFP,cable,patch,etc..) on that port leading to credit loss which forces the switch to issue Link Reset for Credit Recovery.

 

TL

If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution".

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider.
New Contributor
Posts: 2
Registered: ‎05-03-2016

Re: Link Reset issues

Thank you Thomas!
Also, with the Link Reset error, I can see the following event:

S0,P0(23): Required buffer unavailable for the port. req_buf:206 port_buf:106 unused_buf:452 est_buf:106.

I understand that the number of buffers is insufficient. Am I right? Is recommend rasing this number?

Brocade Moderator
Posts: 105
Registered: ‎04-27-2009

Re: Link Reset issues

Hi Werneck,

 

Adding more buffers will not help for these situations and is not necessary. I see there are a lot of Credits assigned to this port, looks to be a long distance ISL?

 

It is possible that you are using all of the Credits on that ASIC that might explain the message. You can check with portbuffershow for available Credits/ASIC.

 

TL

If this provided you with a solution to this issue, please mark it with the button at the bottom "Accept as solution".

Any and all information provided by me is not reviewed, approved or endorsed by Brocade and is provided solely as a convenience for Brocade customers. All systems and all networks are different and unique. If you have a service affecting network problem, please open a TAC service request for service through Brocade, or through your OEM equipment provider.

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