diff --git a/sbin/dump/dump.8 b/sbin/dump/dump.8 index 6ec6abbb93e4..7842a33125c9 100644 --- a/sbin/dump/dump.8 +++ b/sbin/dump/dump.8 @@ -381,7 +381,9 @@ Always start with a level 0 backup, for example: This should be done at set intervals, say once a month or once every two months, and on a set of fresh tapes that is saved forever. .It -After a level 0, dumps of active file systems are taken on a daily basis, +After a level 0, dumps of active file systems (file systems with files +that change, depending on your partition layout some file systems may +contain only data that does not change) are taken on a daily basis, using a modified Tower of Hanoi algorithm, with this sequence of dump levels: .Bd -literal -offset indent @@ -435,7 +437,17 @@ Dump exits with zero status on success. Startup errors are indicated with an exit code of 1; abnormal termination is indicated with an exit code of 3. .Sh BUGS -Fewer than 32 read errors on the file system are ignored. +Fewer than 32 read errors on the file system are ignored, though all +errors will generate a warning message. +This is a bit of a compromise. +In practice it is possible to generate read errors when doing dumps +on mounted partitions if the file system is being modified while the +dump is running. +Since dumps are often done in an unattended fashion using +.Xr cron 8 +jobs asking for Operator intervention would result in the dump dying. +However there is nothing wrong with a dump tape written when this sort +of read error occurs and there is no reason to terminate the dump. .Pp Each reel requires a new process, so parent processes for reels already written just hang around until the entire tape