confusing status/log messages for degraded array

[Joe Rhett]

Soren, I have a quick question.  Am I misreading this, or is it misleading?

During testing of a sil3114 controller (sorry, I know you hate this) 
I pulled out drive 4, which was part of a mirror:

	sandbox# atacontrol list
	ATA channel 0:
	    Master:      no device present
	    Slave:       no device present
	ATA channel 1:
	    Master: acd0 <CD-540E/1.0A> ATA/ATAPI revision 0
	    Slave:       no device present
	ATA channel 2:
	    Master:  ad4 <ST380013AS/3.19> Serial ATA v1.0
	    Slave:       no device present
	ATA channel 3:
	    Master:  ad6 <ST380013AS/3.19> Serial ATA v1.0
	    Slave:       no device present
	ATA channel 4:
	    Master:  ad8 <ST380013AS/3.18> Serial ATA v1.0
    	    Slave:       no device present
	ATA channel 5:
	    Master:      no device present
	    Slave:       no device present

Okay, ad10 is offline.  However atacontrol reports:

	sandbox# atacontrol status 0
	ar0: ATA RAID1 subdisks: ad6 DOWN status: DEGRADED

Does this mean ad6 is up, and the other disk is down?  That would make
sense, but it would be nice to know which disk that is in case one has a
faulty memory or just plain too many systems to manage ;-)

But it gets worse.  So I reinstall the disk and 

	sandbox# atacontrol detach 5
	sandbox# atacontrol attach 5

	Master: ad10 <ST380013AS/3.18> Serial ATA v1.0
	Slave:       no device present

	sandbox# atacontrol rebuild 0

Check the logs and find 

	Dec 12 21:13:39 sandbox kernel: ad10: 76319MB <ST380013AS/3.18> [155061/16/63] at ata5-master SATA150
	Dec 12 21:13:39 sandbox kernel: Opened disk ad10 -> 6

Again, this doesn't tell me which array, and also reads to me as if it is 
rebuilding from ad10 to ad6...  am I reading this wrong?

Just to shorten the thread, I think that clarity would be achieved with:

	sandbox# atacontrol status 0
	ar0: ATA RAID1 subdisks: ad6 ad10(DOWN) status: DEGRADED

	Dec 12 21:13:39 sandbox kernel: Rebuilding array ar0: ad6 -> ad10

-- 
Joe Rhett
Senior Geek
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