I wanted to know if I could extend the size of a RAID5 array on the 3Ware 9650SE, so I tried something.

I first had this:

# tw_cli /c0 show
Unit  UnitType  Status         %RCmpl  %V/I/M  Stripe  Size(GB)  Cache  AVrfy
------------------------------------------------------------------------------
u0    RAID-5    OK             -       -       256K    5587.9    RiW    ON
 
VPort Status         Unit Size      Type  Phy Encl-Slot    Model
------------------------------------------------------------------------------
p0    OK             u0   1.82 TB   SATA  0   -            ST32000542AS
p1    OK             u0   1.82 TB   SATA  1   -            ST32000542AS
p2    OK             u0   1.82 TB   SATA  2   -            ST32000542AS
p3    OK             u0   1.82 TB   SATA  3   -            ST32000542AS
p4    OK             -    1.82 TB   SATA  4   -            ST32000542AS
 
Name  OnlineState  BBUReady  Status    Volt     Temp     Hours  LastCapTest
---------------------------------------------------------------------------
bbu   On           Yes       OK        OK       OK       0      xx-xxx-xxxx

A 4 disk raid 5 and one extra disk.

Then I did this:

# tw_cli /c0/u0 migrate type=raid5 disk=4
Sending migration message to /c0/u0 ... Done.

Then I have this:

# tw_cli /c0/u0 show
 
Unit     UnitType  Status         %RCmpl  %V/I/M  Port  Stripe  Size(GB)
------------------------------------------------------------------------
u0       Migrator  MIGRATING      -       0%      -     -       -
 
su0      RAID-5    OK             -       -       -     256K    5587.9
su0-0    DISK      OK             -       -       p0    -       1862.63
su0-1    DISK      OK             -       -       p1    -       1862.63
su0-2    DISK      OK             -       -       p2    -       1862.63
su0-3    DISK      OK             -       -       p3    -       1862.63
su0/v0   Volume    -              -       -       -     -       50
su0/v1   Volume    -              -       -       -     -       5537.9
 
du0      RAID-5    OK             -       -       -     256K    7450.54
du0-0    DISK      OK             -       -       p0    -       1862.63
du0-1    DISK      OK             -       -       p1    -       1862.63
du0-2    DISK      OK             -       -       p2    -       1862.63
du0-3    DISK      OK             -       -       p3    -       1862.63
du0-4    DISK      OK             -       -       p4    -       1862.63
du0/v0   Volume    -              -       -       -     -       N/A
du0/v1   Volume    -              -       -       -     -       N/A

su0 and du0 are probably source and destination, giving me a new and bigger u0 at the end. But this is going to take a week to migrate, so I won’t know for a while… (edit: I contacted 3Ware support and they said the change in size is only seen after driver reload, which means a reboot in most cases).