All drives develop read errors over time. When you write to these blocks, it may automatically remap them and the errors disappear. Just because you get some read errors doesn't meant the drive is necessarily about to die. But if you develop new bad blocks with any frequency, you might want to replace the drive.
Derick Siddoway [EMAIL PROTECTED] wrote: > Trying to copy a file from one filesystem to another, I kept getting > input/output errors. I noticed these messages in the logs: > > wd1a: uncorrectable data error reading fsbn 768416 of 768384-0 (wd1 bn > 768416; cn 762 tn 5 sn 5), retrying > wd1a: uncorrectable data error reading fsbn 768416 of 768384-0 (wd1 bn > 768416; cn 762 tn 5 sn 5), retrying > wd1a: uncorrectable data error reading fsbn 768416 of 768384-0 (wd1 bn > 768416; cn 762 tn 5 sn 5), retrying > wd1a: uncorrectable data error reading fsbn 768416 of 768384-0 (wd1 bn > 768416; cn 762 tn 5 sn 5), retrying > wd1a: uncorrectable data error reading fsbn 768417 of 768384-0 (wd1 bn > 768417; cn 762 tn 5 sn 6), retrying > wd1a: uncorrectable data error reading fsbn 768417 of 768384-0 (wd1 bn > 768417; cn 762 tn 5 sn 6) > > Okay, so clearly wd1 has some issues (wd1a is the only filesystem on that > disk). I've already started moving the data to a different disk. > > Now, I thought I was going to be alerted to this sort of thing automatically > because of an entry like this one in the crontab: > > 0 * * * * /sbin/atactl /dev/wd0c smartstatus >/dev/null > > However, when I run this by hand, I get > > [EMAIL PROTECTED]:$ sudo /sbin/atactl /dev/wd1 smartstatus > No SMART threshold exceeded > > So clearly, the SMART stuff wasn't going to tell me about this. > > However: > [EMAIL PROTECTED]:$ sudo /sbin/atactl /dev/wd1 readattr > Attributes table revision: 16 > ID Attribute name Threshold Value Raw > 1 Raw Read Error Rate 51 199 0x000000000081 > 3 Spin Up Time 21 123 0x000000001127 > 4 Start/Stop Count 40 99 0x00000000056f > 5 Reallocated Sector Count 140 200 0x000000000000 > 7 Seek Error Rate 51 200 0x000000000000 > 9 Power-on Hours Count 0 73 0x000000004da4 > 10 Spin Retry Count 51 100 0x000000000000 > 11 Unknown 51 100 0x000000000000 > 12 Device Power Cycle Count 0 99 0x00000000056e > 194 Temperature 0 101 0x000000000031 > 196 Reallocation Event Count 0 200 0x000000000000 > 197 Current Pending Sector Count 0 197 0x000000000068 > 198 Off-line Scan Uncorrectable Sect 0 199 0x000000000032 > 199 Ultra DMA CRC Error Count 0 200 0x000000000000 > > I see a number of values that exceed the preset threshholds. > But I see the same kinds of values on the other three drives: > > [EMAIL PROTECTED]:$ sudo /sbin/atactl /dev/wd0 readattr > Attributes table revision: 16 > ID Attribute name Threshold Value Raw > 1 Raw Read Error Rate 51 200 0x000000000000 > 3 Spin Up Time 21 96 0x00000000175f > 4 Start/Stop Count 40 96 0x00000000110f > 5 Reallocated Sector Count 140 196 0x00000000003a > 7 Seek Error Rate 51 200 0x000000000000 > 9 Power-on Hours Count 0 80 0x000000003a71 > 10 Spin Retry Count 51 100 0x000000000000 > 11 Unknown 51 100 0x000000000000 > 12 Device Power Cycle Count 0 99 0x000000000585 > 196 Reallocation Event Count 0 181 0x000000000013 > 197 Current Pending Sector Count 0 200 0x000000000000 > 198 Off-line Scan Uncorrectable Sect 0 200 0x000000000000 > 199 Ultra DMA CRC Error Count 0 200 0x000000000001 > 200 Unknown 51 200 0x000000000000 > [EMAIL PROTECTED]:$ sudo /sbin/atactl /dev/wd2 readattr > Attributes table revision: 16 > ID Attribute name Threshold Value Raw > 3 Spin Up Time 63 200 0x000000001b3c > 4 Start/Stop Count 0 253 0x000000000020 > 5 Reallocated Sector Count 63 253 0x000000000000 > 6 Unknown 100 253 0x000000000000 > 7 Seek Error Rate 0 253 0x000000000000 > 8 Seek Time Performance 187 253 0x00000000aa64 > 9 Power-on Hours Count 0 217 0x00000000b2b8 > 10 Spin Retry Count 157 253 0x000000000000 > 11 Unknown 223 253 0x000000000000 > 12 Device Power Cycle Count 0 253 0x00000000003b > 192 Power-off Retract Count 0 253 0x000000000000 > 193 Load Cycle Count 0 253 0x000000000000 > 194 Temperature 0 253 0x00000000001f > 195 Unknown 0 253 0x000000009dba > 196 Reallocation Event Count 0 253 0x000000000000 > 197 Current Pending Sector Count 0 253 0x000000000000 > 198 Off-line Scan Uncorrectable Sect 0 253 0x000000000000 > 199 Ultra DMA CRC Error Count 0 199 0x000000000000 > 200 Unknown 0 253 0x000000000000 > 201 Unknown 0 253 0x00000000014e > 202 Unknown 0 253 0x000000000000 > 203 Unknown 180 253 0x000000000008 > 204 Unknown 0 253 0x000000000000 > 205 Unknown 0 253 0x000000000000 > 207 Unknown 0 253 0x000000000000 > 208 Unknown 0 253 0x000000000000 > 209 Unknown 0 253 0x000000000000 > 99 Unknown 0 253 0x000000000000 > 100 Unknown 0 253 0x000000000000 > 101 Unknown 0 253 0x000000000000 > [EMAIL PROTECTED]:$ sudo /sbin/atactl /dev/wd3 readattr > Attributes table revision: 16 > ID Attribute name Threshold Value Raw > 3 Spin Up Time 63 204 0x00000000330f > 4 Start/Stop Count 0 253 0x000000000041 > 5 Reallocated Sector Count 63 253 0x000000000000 > 6 Unknown 100 253 0x000000000000 > 7 Seek Error Rate 0 253 0x000000000000 > 8 Seek Time Performance 187 253 0x00000000c738 > 9 Power-on Hours Count 0 211 0x000000006ace > 10 Spin Retry Count 157 253 0x000000000000 > 11 Unknown 223 253 0x000000000000 > 12 Device Power Cycle Count 0 253 0x000000000063 > 192 Power-off Retract Count 0 253 0x000000000000 > 193 Load Cycle Count 0 253 0x000000000000 > 194 Temperature 0 253 0x000000000024 > 195 Unknown 0 253 0x000000000ca3 > 196 Reallocation Event Count 0 253 0x000000000000 > 197 Current Pending Sector Count 0 253 0x000000000000 > 198 Off-line Scan Uncorrectable Sect 0 253 0x000000000000 > 199 Ultra DMA CRC Error Count 0 199 0x000000000000 > 200 Unknown 0 253 0x000000000000 > 201 Unknown 0 253 0x000000000000 > 202 Unknown 0 253 0x000000000000 > 203 Unknown 180 253 0x000000000000 > 204 Unknown 0 253 0x000000000000 > 205 Unknown 0 253 0x000000000000 > 207 Unknown 0 253 0x000000000000 > 208 Unknown 0 253 0x000000000000 > 209 Unknown 0 193 0x000000000000 > 99 Unknown 0 253 0x000000000000 > 100 Unknown 0 253 0x000000000000 > 101 Unknown 0 253 0x000000000000 > [EMAIL PROTECTED]:$ > > I'm not sure what to believe in all of this. The only thing I can clearly > state is that wd1 appears to be going bad, but I can't tell a good way to > be alerted of this fact prior to actually getting input/output errors in > the filesystem. What's the best way to do this short of monitoring? > > > -- > Derick Siddoway And so, the children of the revolution were faced with > the > [EMAIL PROTECTED] age-old problem: it wasn't that you had the wrong kind of > government, which was obvious, but that you had the wrong > kind of people. ( Terry Pratchett, "Night Watch" ) -- Those who can, do. Those who can't, sue.
