On 29/12/11 10:23, Jeremy Thompson wrote:

Here is an excerpt from the dmesg log:

[77832.251754] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x280000 action 0x0
[77832.261281] ata3.00: BMDMA2 stat 0x696d0009
[77832.271043] ata3: SError: { 10B8B BadCRC }
[77832.280933] ata3.00: failed command: READ DMA EXT
[77832.290523] ata3.00: cmd 25/00:00:78:0f:c0/00:04:5b:00:00/e0 tag 0
dma 524288 in
[77832.290526]          res 51/04:6f:78:0f:c0/00:00:00:00:00/f0 Emask
0x1 (device error)
[77832.308903] ata3.00: status: { DRDY ERR }
[77832.318246] ata3.00: error: { ABRT }
[77832.408077] ata3.00: configured for UDMA/100
[77832.408142] ata3: EH complete

The same lines go for ata6 and ata5.  So 3 drives have bad cables?  I
have to mention before starting the reshaping process, I did not see
these errors or at least they were not as pronounced as they are
today.

I'd have a close look at your power supply rather than the cables.

I've seen odd behaviour across multiple drives when they were all under load (as they are in a 
reshape) which went away when I replaced the marginal power supply with something more substantial 
and better engineered.

Regards,
Brad