ata2.00: status: { DRDY }
ata2.00: cmd 61/08:f0:47:00:00/00:00:00:00:00/40 tag 30 ncq 4096 out
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata2.00: status: { DRDY }
ata2: hard resetting link
ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata2.00: configured for UDMA/133
ata2: EH complete
SCSI device sdb: 1953525168 512-byte hdwr sectors (1000205 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: drive cache: write back



solve)

First i would check the cable, make sure its the flat ribbon kind no more than a few inches long, sometimes the longer, round kind gives errors because they are out of spec.

There is a sector error there, so check what SMART says:


sudo smartctl -H /dev/sdf

This should give you a quick response as to SMART finding anything bad in the past or now.

Also do:

sudo smartctl -A /dev/sdf

post the values table that it gives you, you should be able to see though if there are a lot of some specific errors.

Probably a good idea to have SMART run an extended selftest on the drive anyway:

sudo smartctl --test=long -C /dev/sdf

This will run the extended selftest, and it will tell you how long it takes. When it is done you can get the results like this:

sudo smartctl --log=selftest /dev/sdf


centos)
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