This was not something I wanted and I needed to disable it. In order to do so I had to edit /kernel/drv/fp.conf file and tell Solaris not to enable MPxIO on internal disks. So I added the following line at the end of fp.conf file:

name="fp" parent="/pci@8,600000/SUNW,qlc@4" port=0 mpxio-disable="yes";

This line tells Solaris to disable MPxIO on port 0 for all devices whose parent device is /pci@8,600000/SUNW,qlc@4. Of course, similar line should be added for all HBA’s and ports you do not want to have under MPxIO’s control. You can get the parent device from your /var/adm/messages file or from device links pointing to the internal disks. Here is a partial list of device links:

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lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s0 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:a
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s1 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:b
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s2 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:c
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s3 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:d
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s4 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:e
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s5 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:f
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s6 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:g
lrwxrwxrwx 1 root other 70 Jun 12 11:50 c1t0d0s7 -> ../../devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w2100002037c3e2ef,0:h

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