Symptoms

RE (GiGE) port link is down.RE port SRDF link is down and also shows NIC State: DOWN and NIC Link State: DOWNSRDF link is down. 

Cause

Customer environment using Priority Flow Control instead of Pause Flow Control (see KB article 173193 for more information). Internally, many network errors and occasional link drops are witnessed. The RainstormE drops packets from the link because it cannot provision Rx buffers fast enough. In extreme situations, it can leave an RE port in a bad state. The code always attempts to recover from this but on rare occasions may fail to do so. The result leaves the RE port to lose links and show:NIC State: DOWNNIC Link State: DOWN

Resolution

Contact the Support Center for assistance and quote this article ID if you think you have encountered this issue.Workaround:The Support Center must mock replace the director. Permanent Solution Turn on Hardware Compression.Stop using Priority Flow Control and use Pause Flow Control on all switches on both sides of the links.Discuss using Jumbo Frames 9000 MTU if all equipment can support it (links will drop and potentially stay down if anything along the path does not support this).

Support Cases