I'm backing up a linux box to a NAS mounted via NFS. I'm using rsync (as part of a scheme along the lines of http://www.mikerubel.org/computers/rsync_snapshots/ with hard-links). That is I ssh into machine_being_backed_up, start my rsync command, it backs up files for about an hour or so, and then freezes the server (e.g., needs to be physically rebooted; which is very inconvenient as the servers in another building across town so takes time to reboot) the error at the end being (with actual names anonymized):
some/path/file1.gz rsync: read errors mapping "/home/some/path/file1.gz": Input/output error (5) some/path/file2.gz rsync: read errors mapping "/home/some/path/file2.gz": Input/output error (5) some/path/file3.gz
This is likely indicating that the hard drive on the machine I'm trying to back up has some faulty sectors, correct? Or could that error arise from the NFS connection being too slow or choosing the wrong options when mounting my NFS drive (mounting with rw,soft,intr options)? Is there anyway to make these input/output errors just skip/fail those files, and not freeze the system (so I don't have to go across town to reboot the server)?
Update: I turned on SMART yesterday and ran short and long selftests yesterday that reported no errors (yesterday I couldn't mention this as the long test finished around 7p and the computer crashed around midnight so I could login until this morning when I could on-site reboot).
Also I tried rsync-ing the in question files to a different partition on the same drive and didn't get any errors. I'm now trying to rsync directly to the NAS (rather than mounting the NAS using NFS).
Update (Oct 3rd): I've moved the hard drive to a different machine and its been ~2 weeks with no errors. While in the old machine there were daily errors of this type. I'm guessing motherboard or memory errors in the other machine (haven't had the time to fully diagnose and pinpoint the problem).