If no arguments are given, the key is assumed to be 9u and a default file system is dumped to the default tape.
Dump requires operator intervention on these conditions: end of removable disk or tape, end of dump, removable disk or tape write error, removable disk or tape open error or disk read error (if there are more than a threshold of 32). In addition to alerting all operators implied by the n key, dump interacts with the operator on dump's control terminal at times when dump can no longer proceed, or if something is grossly wrong. All questions dump poses must be answered by typing ``yes'' or ``no'', as appropriate.
Since making a dump involves a lot of time and effort for full dumps, dump checkpoints itself at the start of each tape or removable disk volume. If writing the tape volume fails for some reason, dump will, with operator permission, restart itself from the checkpoint after the old tape has been rewound and removed, and a new tape has been mounted. If writing the removable disk fails for some reason, dump will prompt the operator to restart from the checkpoint after the old removable disk has been ejected and the new removable disk has been inserted.
Dump tells the operator what is going on at periodic intervals, including usually low estimates of the number of blocks to write, the number of removable disks or tapes it will take, the time to completion, and the time to the disk or tape change. The output is verbose, so that others know that the terminal controlling dump is busy, and will be for some time.
Dump looks in /etc/swaptab for swapfiles that reside on the filesystem being dumped. If any matches are found, those files are not included in the dump.
Now a short suggestion on how to perform dumps. Start with a full level 0 dump
dump 0un
Next, dumps of active file
systems are taken on a daily basis,
using a modified Tower of Hanoi algorithm,
with this sequence of dump levels:
3 2 5 4 7 6 9 8 9 9 ...
For the daily dumps, a set of 10 tapes per dumped file system
is used on a cyclical basis.
Each week, a level 1 dump is taken, and
the daily Hanoi sequence repeats with 3.
For weekly dumps, a set of 5 OD's or tapes per dumped file system is
used, also on a cyclical basis.
Each month, a level 0 dump is taken
on a set of fresh OD's or tapes that is saved forever.
For example, to perform a level X dump to the internal floppy disk, use a command of the following form:
dump XOf 2.6 /dev/rfd0a
dump Xfs... /dev/nrxt0 1200000 ...
(or similarly with /dev/rxt0).
/dev/rsd0a default filesystem to dump from /dev/rxt0 default tape unit to dump to /dev/rod? default optical disk /dev/rfd0a internal floppy disk /etc/dumpdates new format dump date record /etc/fstab dump table: file systems and frequency /etc/group to find group operator
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.
Dumps made with dump can't be restored by other vendors' restore programs. In order to make dumps that can, use dump.old.
It is hard to measure an optical disk in terms of tenths of inchs and size of inter-record gap. A multi-machine, multi-media solution should be sought.
Dump should have some file that it consults that contain inode numbers, names of files and directories, and names of users and/or groups to not dump to removable disk/tape. This feature would come in especially handy to avoid dumping /usr/man/cat, /NextLibrary, and /NextApps. System administrators can get around this by writing a program that changes the modification time for these files.
Because of the interworkings of rmt and rdump, it is only possible to run rdump from one NeXT machine to another. This is in part due to the fact that the ioctls for the removable disk differ from the mag tape ioctls available with rmt, and in part due to the fact that NFS does not implement remote device ioctls.
Fewer than 32 read errors on the filesystem are ignored. Each removable disk or reel requires a new process, so parent processes for reels already written just hang around until the entire tape is written.
Dump with the W or w options does not report filesystems that have never been recorded in /etc/dumpdates, even if listed in /etc/fstab.
It would be nice if dump knew about the dump sequence, kept track of the tapes scribbled on, told the operator which tape to mount when, and provided more assistance for the operator running restore.
Created by unroff & hp-tools. © somebody (See intro for details). All Rights Reserved. Last modified 11/5/97