Basically the filer was "too busy" tor respond back. According to NOW, a one time occurrance may not be cause for concern, repeating alerts should be addressed. Basically the filer told a host that the SCSI queue was full and it would have to resend.
Start off by checking to see if there was a workload increase on Saturday, something that is hopefully really outside the normal load. If not, you may be exceeding the ability of the storage system, and you need to rebalance some ops.
https://kb.netapp.com/support/index?page=content&id=2011313
- Scott
