RAID 1 rebuild
 

Hi,

I have a RAID1-question. I have a RAID1 builded in
this way:

md1 : active raid1 hdc7[1] hda7[0]
2048192 blocks [2/2] [UU]

md0 : active raid1 hdc1[1] hda1[0]
30716160 blocks [2/2] [UU]

md0 is "/" and md1 is the "/tmp part.

I tested a one-disk failure: I have turned-on
my PC with only hdA and I obtain a RAID degraded
system ... this OK.

The strange think appear when I reattach hdC an I
restart my system. I had this situation:

md1 : active raid1 hdc7[1] hda7[0]
2048192 blocks [2/1] [U_]

md0 : active raid1 hdc1[1] hda1[0]
30716160 blocks [2/1] [_U]

... WAIT a moment ... but how is this possibile?
md1 have the safe part. on hdC while md0 have
the safe part. on hdA?!?!? ... but safe data
are on hdA only!!!!

How can I force raid-engine to use ONLY hdA to
rebuild RAID1 on hdC?

TIA
Roberto Colmegna

Yeah I dunno how you got that to happen, but you can't really force it to do otherwise. Maybe MD1 being your /tmp it was so unused when the drive got reconnected it actually looked like the newer copy.

Despite what you posted above maybe your reading it backwards? On mine for example, despite the drives being listed as hde, hdg for both raids I still get this from looking at /proc/mdstat

md1 : active raid1 hde5[0] hdg5[1]
1999744 blocks [2/2] [UU]

md0 : active raid1 hdg2[1] hde2[0]
76150720 blocks [2/2] [UU]


the hde, and hdg are reversed for each raid and I don't really know why.