We've got a VM with 7 disks on 3 different SCSI Paravirtual controllers in VMware ESX 5.5 but they are not ordered as expected within the Linux VM.
Hard disk 1 0:0 9GB
Hard disk 2 0:1 7GB
Hard disk 3 0:2 3GB
Hard disk 4 1:0 660GB
Hard disk 5 1:1 510GB
Hard disk 6 1:2 145GB
Hard disk 7 2:0 3GB
In vSphere client the disks are ordered as expected, but in the VM (SLES 11SP4) strange things happened.
The 3rd Paravirtual controller in VMware with the 3GB disk on 2:0 is in linux the 2nd controller and the 2nd controller in VMware is the 3rd in linux.
# ls -ld /sys/block/sd*/device/scsi_device/*
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sda/device/scsi_device/0:0:0:0
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sdb/device/scsi_device/0:0:1:0
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sdc/device/scsi_device/0:0:2:0
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sdd/device/scsi_device/1:0:0:0 <- this is the 7th disk in vSphere client
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sde/device/scsi_device/2:0:0:0
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sdf/device/scsi_device/2:0:1:0
drwxr-xr-x 3 root root 0 Aug 30 00:49 /sys/block/sdg/device/scsi_device/2:0:2:0
# fdisk -l |grep "Disk /dev/"
Disk /dev/sda: 9663 MB, 9663676416 bytes
Disk /dev/sdb: 7516 MB, 7516192768 bytes
Disk /dev/sdc: 3221 MB, 3221225472 bytes
Disk /dev/sdd: 3221 MB, 3221225472 bytes --> should be SDG
Disk /dev/sde: 708.7 GB, 708669603840 bytes --> should be SDD
Disk /dev/sdf: 547.6 GB, 547608330240 bytes --> should be SDE
Disk /dev/sdg: 155.7 GB, 155692564480 bytes --> should be SDF
# lspci
03:00.0 Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)
04:00.0 Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)
1b:00.0 Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)
At this moment everything is working fine but i'm looking for the reason why the disks are not ordered right, anyone have an explanation?