Recommendations for servers running SATA drives [hot-swap]

[Miroslav Lachman]

Jeremy Chadwick wrote:
> On Mon, Sep 29, 2008 at 05:25:32PM +0200, Miroslav Lachman wrote:
> 
>>It was about year ago with Asus and Sun Fire X2100. I don't have Asus  
>>servers now (all returned as reclamation). Now I am running one X2100  
>>and about ten X2100 M2. I have one spare X2100 M2, so if somebody have  
>>exact order of commands used to "hot-swap" the disk, I can test it in  
>>few days.
> 
> 
> I believe the correct order of operation is to do a "detach" on the
> channel before physically removing the disk, insert the new disk, then
> do "attach" on the same channel.  "list" should be done afterwards to
> ensure the new disk shows up.
> 
> If you want me to verify for certain, I have a test box built in the
> other room which has a SATA hot-swap backplane on it.
> 
> I've also seen cases where the "attach" works, but upon doing "list",
> the old disk ID/string is still shown.  In this case I had to do a
> "detach", remove the disk, insert the new disk, "reinit", then an
> "attach" for things to work.
> 
> Finally, I've also seen the kernel panic or hard-lock after running
> "reinit", but this may have had something to do with Intel MatrixRAID.

Today I was replacing disk in one Sun Fire X2100 M2 so I tried 
hot-swapping. It was as you said: atacontrol detach ata3, replace the 
HDD, atacontrol attach ata3 and new disk is in the system. I tried it 3 
times to be sure that it was not coincidence - no panic was produced ;o)
So in this case, hot-swapping on Sun Fire X2100 M2 with FreeBSD 7.0 i386 
works.

Miroslav Lachman


# atacontrol list
ATA channel 0:
     Master:      no device present
     Slave:       no device present
ATA channel 1:
     Master:      no device present
     Slave:       no device present
ATA channel 2:
     Master:  ad4 <Hitachi HDP725050GLA360/GM4OA52A> Serial ATA II
     Slave:       no device present
ATA channel 3:
     Master:  ad6 <Hitachi HDP725050GLA360/GM4OA52A> Serial ATA II
     Slave:       no device present

# atacontrol detach ata3
subdisk6: detached
ad6: detached
GEOM_MIRROR: Device gm0: provider ad6 disconnected

# atacontrol list
ATA channel 0:
     Master:      no device present
     Slave:       no device present
ATA channel 1:
     Master:      no device present
     Slave:       no device present
ATA channel 2:
     Master:  ad4 <Hitachi HDP725050GLA360/GM4OA52A> Serial ATA II
     Slave:       no device present
ATA channel 3:
     Master:      no device present
     Slave:       no device present

## [old disk was physically removed]

## [new disk was physically inserted]

# atacontrol attach ata3
ata3: [ITHREAD]
ad6: 953869MB <SAMSUNG HD103UJ 1AA01113> at ata3-master SATA300
Master:  ad6 <SAMSUBF HD103UJ/1AA01113> Serial ATA II
Slave:       no device present

# atacontrol list
ATA channel 0:
     Master:      no device present
     Slave:       no device present
ATA channel 1:
     Master:      no device present
     Slave:       no device present
ATA channel 2:
     Master:  ad4 <Hitachi HDP725050GLA360/GM4OA52A> Serial ATA II
     Slave:       no device present
ATA channel 3:
     Master:  ad6 <SAMSUNG HD103UJ/1AA01113> Serial ATA II
     Slave:       no device present