During IBM SVC (http://www.ibm.com/storage/svc) installation, FC links between nodes and brocade switches were not able to negociate.
The negociate starts but never ends and the switch disable the port with no apparent reason.
I don’t had this problem with older 4GB switches.
Brocade switch firware were just upgraded to 6.3.0b. By reding carefully the release note we can find the following information (Available here) :
Depending on the fulfillment method, the default fill word may be set to IDLE or ARB(FF).
The fill word is changed using the portcfgfillword command. Although the fill word is always
IDLE when ports log in at less than 8Gb/sec, executing the portcfgfillword command is
disruptive regardless of what speed the ports log in at. Brocade recommends ARB(FF) except
for the following devices which require the fill word to be set to IDLE:
• IBM SVC
• EMC DASD
I fix the problem by setting portcfgfillword on all ports.
Good to know : This is not a new feature but the default value where previously set to IDLE.