In my experience, that would usually be a connectivity problem, most frequently bad fiber connections or marginal SFPs. Assuming you have FC switches, check the port error counters on the switch (Brocade porterrshow). You should also be able the to check errors on the AIX side with fcstat.
This redpaper also has some useful information on troubleshooting SFPs: https://www.redbooks.ibm.com/abstracts/redp5699.html
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Vincent Greene
IT Consultant
Technology Expert labs
IBM
Vincent.Greene@ibm.comThe postings on this site are my own and don't necessarily represent IBM's positions, strategies or opinions.
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