scott@ukecc.UUCP (Scott Sendlein) (03/11/86)
I have an AT&T 3B20S and need info and recommendations regarding backup of my system with tapes. I am under the impression that the standard Sys V tools are unsuitable. Tar does not seem to work reliably, volcopy and dd are wasteful, and cpio does not provide for multiple tape backups. Cpio would seem to me to be the most likely candidate for doing incrementals if it weren't for the fact that it does not handle mult. tapes which means that I must determine how much stuff in a particular system you can put on one tape. This obviously could be handled with a little shell programming but I really hate re-inventing the wheel. I have heard rumours that there is a program called fcpio that stands for 'fixed-cpio' and is supposed to take care of this. If so, where can I find it? I would also appreciate recommendations as to the frequency and nature of backups that others have been using. (right now I am doing monthly full backups to hard disk, I have 6 300 mb drives, but now my user load is big enough to require at least weekly and possibly daily incr.) Thank you, -- Scott Sendlein UUCP: ihnp4!cbosgd!ukma!ukecc!scott Voice: (606) 257-1752 Rm. 280 Anderson Hall Univ. of Kentucky College of Engr. Lexington, KY 40506-0046
twh@mb2c.UUCP (Tim Hitchcock) (03/14/86)
> I have an AT&T 3B20S and need info and recommendations regarding backup of > my system with tapes. I am under the impression that the standard Sys V > tools are unsuitable. Tar does not seem to work reliably, volcopy and dd > are wasteful, and cpio does not provide for multiple tape backups. Cpio > would seem to me to be the most likely candidate for doing incrementals if > it weren't for the fact that it does not handle mult. tapes which means that > I must determine how much stuff in a particular system you can put on one tape. > This obviously could be handled with a little shell programming but I really > hate re-inventing the wheel. I have heard rumours that there is a program > called fcpio that stands for 'fixed-cpio' and is supposed to take care of this. > If so, where can I find it? I would also appreciate recommendations as to the > frequency and nature of backups that others have been using. (right now I am > doing monthly full backups to hard disk, I have 6 300 mb drives, but now my > user load is big enough to require at least weekly and possibly daily incr.) > > Thank you, > > -- > Scott Sendlein > > UUCP: ihnp4!cbosgd!ukma!ukecc!scott > Voice: (606) 257-1752 > Rm. 280 Anderson Hall > Univ. of Kentucky > College of Engr. > Lexington, KY 40506-0046 *** REPLACE THIS LINE WITH YOUR MESSAGE *** When I was a 3B20S system administrator I set up this backup procedure. It is not foolproof, but I didn't like hanging around to take care of dumps, or have the clerk call me at home with problems. One requirement. You must have a spare disk with lots of space. One big advantage - the system need never come down. 1) Create a backup filesystem to your liking on the spare disk drive. 2) Set up a cpio based backup of your production filesystems. * You MUST use -u (unconditional copy) on the root FS, or special files will not copy 3) Put the backup command in cron to run in the wee hours. Don and Doff the spare drive mount and umount the backup FS (if desired) 4) Do a tape dump (volcopy or that new cpio ) during the day (or whenever you are on site) No need to bring the machine down as you can dump the data from the spare disk, which in not in use. I only ran a tape dump once a week (Wednesday morning while I was on site) used it for two years without a problem. Since cpio copies files and doesn't mess with raw disk blocks, you can have the system active while ALL backup procedures are running. (I would not recommend a disk cpio during the day or whenever your users are busy for performance sake, but the tape volcopy was not TOO bad). Most requests for the restoring of files are from users that removed a file by accident. You can restore any file from any terminal without mounting a tape. A tape restore would only be necessary if both the production disk and the backup disk went bad. (With the exception of getting a file that was VERY old. Of course you must keep an eye on your backup disk space. When it gets full, you must wipe out some of the files. You could either remake the backup FSs, or use the find command to select certain types of files for removal. Either way a shell script in cron is all it takes). When my backup filesytem was full, I would remake the backup FS night after the tape dump. In regard to the cpio question, there is a new cpio command on the 3B2 called "newcpio". If you would like a copy of my sh script, I can forward it to you. Tim