After a XenServer Host reboot, some of the paths are not visible when typing the command multipath -ll

 

1. Login into XenServer Host command line using putty
2. Confirm how many paths are visible for the LUN by typing:

            #multipath -ll

1. Check if the missing paths are visible under /proc/scsi/scsi using H:B:T:L (Host:Bus:Targe:Lunid). If the paths are not visible there, then we need to rescan the bus running #rescan-scsi-bus.sh
2. If still multipath -ll does not show the new paths, run the below command to refresh its paths status

                     # multipath -v4

After performing above steps, still if you don't see the information, then there is some issues with the mapping on backend switch/SAN. Checking for zoning/mapping.

Problem Cause

Kernel has not refreshed the new paths which came available in later stages of booting