What to call ZFS vdev that won't change?

Good news is you can change the vdev configuration scheme by exporting and re-importing your pool. (from ZFS on Linux docs)

admin@Test-ZFS:~$ sudo zpool status tankz
  pool: tankz
 state: ONLINE
  scan: resilvered 15K in 0h0m with 0 errors on Tue Feb 25 16:36:18 2014
config:

        NAME        STATE     READ WRITE CKSUM
        tankz       ONLINE       0     0     0
          raidz1-0  ONLINE       0     0     0
            sdc     ONLINE       0     0     0
            sde     ONLINE       0     0     0
            sdd     ONLINE       0     0     0

errors: No known data errors

admin@Test-ZFS:~$ sudo zpool export tankz
admin@Test-ZFS:~$ sudo zpool import -d /dev/disk/by-id tankz
admin@Test-ZFS:~$ sudo zpool status tankz
  pool: tankz
 state: ONLINE
  scan: resilvered 15K in 0h0m with 0 errors on Tue Feb 25 16:36:18 2014
config:

        NAME                                       STATE     READ WRITE CKSUM
        tankz                                      ONLINE       0     0     0
          raidz1-0                                 ONLINE       0     0     0
            ata-VBOX_HARDDISK_VB3b2901c3-c7700ec9  ONLINE       0     0     0
            ata-VBOX_HARDDISK_VB4ad696a7-d3e6b542  ONLINE       0     0     0
            ata-VBOX_HARDDISK_VBbed2a908-5ddcaedb  ONLINE       0     0     0

errors: No known data errors

You're not supposed to use /dev/sdX names for ZFS pools in cases where the SCSI device names can change. See the options under /dev/disk...

[root@Davalan /dev/disk]# cd by-
by-id/   by-path/ by-uuid/ 

I usually use the /dev/disk/by-id entries for my Linux zpools...

# zpool status
  pool: vol1
 state: ONLINE
  scan: scrub repaired 0 in 1h44m with 0 errors on Sat Jul  6 13:12:06 2013
config:

        NAME                               STATE     READ WRITE CKSUM
        vol1                               ONLINE       0     0     0
          mirror-0                         ONLINE       0     0     0
            scsi-35000c5003af99fa7         ONLINE       0     0     0
            scsi-35000cca0153ec2d0         ONLINE       0     0     0
          mirror-1                         ONLINE       0     0     0
            scsi-35000cca01540e340         ONLINE       0     0     0
            scsi-35000cca01540e298         ONLINE       0     0     0
        cache
          ata-STEC_M8IOPS-50_STM000136649  ONLINE       0     0     0

and...

[root@Davalan /dev/disk/by-id]# ls -1
ata-STEC_M8IOPS-50_STM000136649
ata-STEC_M8IOPS-50_STM000136649-part1
ata-STEC_M8IOPS-50_STM000136649-part9
scsi-35000c5003af99fa7
scsi-35000c5003af99fa7-part1
scsi-35000c5003af99fa7-part9
scsi-35000cca0153ec2d0
scsi-35000cca0153ec2d0-part1
scsi-35000cca0153ec2d0-part9
scsi-35000cca01540e298
scsi-35000cca01540e298-part1
scsi-35000cca01540e298-part9
scsi-35000cca01540e340
scsi-35000cca01540e340-part1
scsi-35000cca01540e340-part9
scsi-SATA_STEC_M8IOPS-50_STM000136649
scsi-SATA_STEC_M8IOPS-50_STM000136649-part1
scsi-SATA_STEC_M8IOPS-50_STM000136649-part9
wwn-0x5000a720300411f7
wwn-0x5000a720300411f7-part1
wwn-0x5000a720300411f7-part9
wwn-0x5000c5003af99fa7
wwn-0x5000c5003af99fa7-part1
wwn-0x5000c5003af99fa7-part9
wwn-0x5000cca0153ec2d0
wwn-0x5000cca0153ec2d0-part1
wwn-0x5000cca0153ec2d0-part9
wwn-0x5000cca01540e298
wwn-0x5000cca01540e298-part1
wwn-0x5000cca01540e298-part9
wwn-0x5000cca01540e340
wwn-0x5000cca01540e340-part1
wwn-0x5000cca01540e340-part9