multipath issue with scsi
 

Hi All,

I am seeing following msg in /var/log/messages:

I am trying to understand the issue that why it is appearing. I googled but could not find useful info.
my understanding of the issue: might be multipath fails to map device but don't know why.

please help me understanding the issue.

Thanks.

Would help if you told us what version/distro of Linux you're using, with what kind of SCSI drives. And what do you have in your multipath.conf file? Google turns up lots of suggestions...but the biggest question right now is, do you actually HAVE drives that can benefit from multipathing?? It's typically used on SAN's or iSCSI devices, not LOCAL SCSI. Do a "multipath -ll" to find out more info.

https://forums.oracle.com/forums/thr...readID=2165591
https://access.redhat.com/knowledge/solutions/60885
https://access.redhat.com/knowledge/solutions/78013
https://access.redhat.com/knowledge/...ath/index.html

Often you have both "local" and "SAN' drives on the same system and you're using multipath for redundancy and performance for the latter. However, multipathd will look at all your disks whether local or SAN so you have modify the multipath configuration so it does NOT try to multipath your local drives. Local drives would include any USB attachments you make. I've seen issues with USB drives not working when plugged in because the daemon tried to manage them.

Oh yeah, been there, found that ... ;)
Use the blacklist option in multipath.conf eg https://access.redhat.com/knowledge/...procedure.html