Time BB credit zero

[mmax]

Hello.
I have problem, that we installed SilkWorm 4/32 and 4/16 switches but on the ISL ports counter tim_txcrd_z is increasing.
stat_wtx 77768328 4-byte words transmitted
stat_wrx 78651020 4-byte words received
...
tim_txcrd_z 6368 Time BB credit zero

We checked cables but we didn't found any problem after measurement.
What should be problem?
Thank you for answer
Michal

[Amar_Joshi]

Michal,

In my view 6368 tim_txcrd_z is still tolerable compared to what traffic you have on ISL. None the less, in order to resolve the issue, i don't think cable would have caused this. Probably you wanna look into the ports which are generating the traffic, try to see if any port settings are differing from others or anything significantly changed for any specific port.

[mmax]

i checked all ports settings across fabric.
I found on the other switch not exact same ISL buffer settings

switch12# portbuffershow
User Port Lx Max/Resv Buffer Needed Link Remaining
Port Type Mode Buffers Usage Buffers Distance Buffers
---- ---- ---- ------- ------ ------- --------- ----------
0 E - 8 17 17 <2km


from the 2nd side of ISL I see output like

switch13#
2 E - 8 26 26 2km

How could I setup manually buffer credits per ISL port? We don't have Extended fabric license.

[mmax]

setted portcfglongdistance 0 LE to enable more buffer credits, also path distance is increased