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Rx CRC and Rx Jabber

  • 21 February 2017
  • 4 replies

Userlevel 2

We're experiencing infrequent CRC/Jabber errors on a particular interface between 2 670v-48x switches. Switches are running code version patch 1-18 at the moment. They run our iSCSI network.

Both ports connected together, 49-49 on each switch experience the errors, connected via pre terminated copper cable, Q+CR4_3m.

I have checked that the cable is not in the vicinity of electrical cables to try to rule out interference.

Would it simply be a bad cable/module on the cable that causes this? We've had to change this before so I'm concerned it may be the slot(s) in the switch(es) itself?

Any thoughts welcome :)


4 replies

Userlevel 2
Rx Jabber can increment under the following situations -
* packet data length exceeds configured MTU (1518 for non-jumbo and 9018 for jumbo) and/or
* has a bad CRC.

Most likely, it will be a Layer 1 related problem and as a first step as Karthik suggested, it would be best to replace the cable.
I have a similar issue. Can someone give a hint on resolution.
Userlevel 7
Hello Ian, are you still having trouble with CRC errors?
Userlevel 6
Hi Ian, I would suggest the first and easy step is to swap the DAC cable and see if the RX-errors are changes to the other end.