If you need to check that your HDLM (Hitachi) SAN paths are definately using separate HBA’s (for resilience reasons) read on….
Pick a disk that you want check, in my example I’m going to pick on hdisk151. This disk is also mirrored to another disk in the same volume group that is physically on a different SAN, but I just want to check that hdisk151 can use one of two adapters to reach the storage array.
Use the dlnkmgr view command to check the PathName used.
root@impact_lm:/ > dlnkmgr view -path| grep hdisk151
000302 08.0G.0000000000150000.0029 HITACHI .OPEN-V .0025428 005001 2A Online Own 67 0 0 hdisk151
000303 08.0H.00000000000B0000.0029 HITACHI .OPEN-V .0025428 005001 1A Online Own 66 0 0 hdisk151
The figures in bold indicate the HBA adapter that each path uses, so now we run: –
root@impact_lm:/ > lsdev -Ccadapter
ent0 Available 06-08 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
ent1 Available 06-09 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
ent2 Available 09-08 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
ent3 Available 09-09 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
fcs0 Available 07-08 FC Adapter
fcs1 Available 0A-08 FC Adapter
fcs2 Available 0G-08 FC Adapter
fcs3 Available 0H-08 FC Adapter
fcs6 Defined 0L-08 FC Adapter
fcs7 Defined 0L-09 FC Adapter
sisscsia0 Available 05-08 PCI-X Ultra320 SCSI Adapter
sisscsia1 Available 08-08 PCI-X Ultra320 SCSI Adapter
vsa0 Available LPAR Virtual Serial Adapter
vscsi0 Available Virtual SCSI Client Adapter
The HBA adapter numbers are shown above along with the devices actually being used. We can see that one path uses fcs2 and the other uses fcs3.
But, which one is the active, and which the passive?
root@impact_lm:/ > lsdev -Cc disk | grep hdisk151
hdisk151 Available 0G-08-02 Hitachi Disk Array (Fibre)
Now, we can see that fcs2 is the active adapter. The hitachi driver software will automatically use the passive path (fcs3), should the paths on fcs2 fail.