Page 1 of 1

Link Down on QSFP+ Ports CRS326-24S+2Q+RM

Posted: Mon Sep 27, 2021 12:06 pm
by ssn

I've an odd issue with the 40Gbit QSFP+ in our setup. For now I've reduced the setup to the following simple setup and the issue still occur.

2 x CRS326-24S+2Q+RM running lateste stable RouterOS 6.48.4. Both reset to default config (/system reset-configuration).
interconnected using 2 x Q+DA0001 cable (Our actual setup is a more complex MSTP Spanning Tree).
Switch 1 qsfpplus2-1 -------------------|
         qsfpplus2-1 ------------|      |
                                 |      |
                                 |      |
Switch 2 qsfpplus2-1 ------------|      |
         qsfpplus1-1 -------------------|
If I now pull the cable from Switch 1 qsfpplus2-1 not only this link goes down. But one second later also the other one goes down.
In the log I can see only this:
00:33:43 interface,info qsfpplus2-1 link down
00:33:44 interface,info qsfpplus1-1 link down
I've tested using different hardware (switches / cables) but the issue does allways occur, so it doesn't seem to be a hardware defect. Does someone see similiar behaviour? How can this be fixed?