I have a ReadyNAS Pro Business edition RNDP6350. Once a week I attach an external USB hard drive to the front USB port and backup the entire C partition. This has worked without issue for a couple of years now.
Recently the backup job fails to complete, presenting an error message like this
Backup failed. Mon Oct 15 11:44:29 GMT 2012.
Reason for failure: Error encountered copying data from source path ==> /USB_HDD_27/backup due to unknown reason. Please see log.
Note the last line written to the log appears to be truncated. If the same job is re-run it will fail to complete again but not at the same file.
I have recently updated the firware in the device to the latest version and suspect that the problem may be related to that. However, I have also had to replace one of the hard disks recently too.
I also run daily backup jobs to another ReadyNAS on the network, these continue to run correctly.
Edit: Problem solved! I'm using a 2.5 HDD and I was powering it with a single USB cable. Once I plugged in the Y-cable to give it more power, everything works fine.
Yes, it has a issue for backup to USB on 4.2.21 and 4.2.22, we found root cause , cp process cause out of memory when doing backup to USB, it will fixed 4.2.23, you may use resync to backup now, it does not use cp process. 1, Enable Rsync in Servers/Standart Files Protocals 2, Open share list, enable Read/Write in Rsync of USB Share. 3, Add a backup job, set source as remote rsync, input your NAS's IP in Host and Path is USB folder name. 4, Set destination as a share folder.
