pwolfe@kailand.kai.com (Patrick Wolfe) (12/29/89)
> From: Kian-Tat Lim <ktl@csvax.caltech.edu> > Subject: Network backup suggestions? > > We have a 95% full 500 megabyte filesystem on our 4D/240 that > we would (very much) like to backup regularly. The Iris only has a > cartridge tape drive, but another of our machines (running a fairly > standard 4.3 BSD) has a 6250 bpi 9 track. The two machines are > connected by a lightly-loaded Ethernet. > > 1) The filesystem is NFS mounted on the BSD machine. We would > thus be able to use dump if we enabled root access to the remote > filesystem. Are there any additional security holes we would > introduce by doing this? If at all possible, try to forget about backing up with NFS access. NFS is fine for normal file access, but for really I/O intensive programs that access lots of files (like backups), it's way too slow, and bogs down both machines. > 4) Any other suggestions? Try GNU tar. You can pick it up via anonymous ftp from expo.lcs.mit.edu (something like /pub/gnu/tar1.07.Z). It uses the /etc/rmt program (same as BSD's rdump), allowing your IRIS to access a tape drive on a BSD machine. It also includes the rmt program, so you can access the IRIS cartridge tape from a remote machine. You need no special priviledges to compile and use it. There are all kinds of options in GNU tar that make it an effective tool for backups. I use it on all of our System V machines (including two Iris 4D's) for monthly full backups, dumping across our network to the 2.3 Gb 8mm cartridge tape drive installed on a BSD 4.3 machine. I also use it for daily incremental backups on the BSD machines. If you have trouble compiling it, check the options in the "port.c" file. One other (beneficial, I think) side effect of GNU tar over regular AT&T tar. On BSD systems, if you extract files from a tar archive, you become the owner of all the new files (unless you are root). On System V, AT&T tar restores the original owner (because you are allowed to give away files), in which case you may not have access to the new files (especially if the tar archive came on mag tape from another site). GNU tar doesn't restore the original owner, unless you are root, so it acts just like BSD's tar from the user's standpoint. -- Patrick Wolfe (pwolfe@kai.com, ...!kailand!pwolfe) System Manager, Kuck & Associates
ciemo@bananapc.wpd.sgi.com (Dave Ciemiewicz) (12/30/89)
In article <8912291517.AA02333@kailand.kai.com>, pwolfe@kailand.kai.com (Patrick Wolfe) writes: > > One other (beneficial, I think) side effect of GNU tar over regular AT&T tar. > On BSD systems, if you extract files from a tar archive, you become the owner > of all the new files (unless you are root). On System V, AT&T tar restores the > original owner (because you are allowed to give away files), in which case you > may not have access to the new files (especially if the tar archive came on mag > tape from another site). GNU tar doesn't restore the original owner, unless > you are root, so it acts just like BSD's tar from the user's standpoint. > The BSD functionality of not giving away files can be accomplished with AT&T tar by using the -o (do not chown or chgrp files). You don't need a special tar to accomplish this. --- Ciemo
vjs@rhyolite.wpd.sgi.com (Vernon Schryver) (12/30/89)
In article <8912291517.AA02333@kailand.kai.com>, pwolfe@kailand.kai.com (Patrick Wolfe) writes: |... | On BSD systems, if you extract files from a tar archive, you become the owner |of all the new files (unless you are root). On System V, AT&T tar restores the |original owner (because you are allowed to give away files), in which case you |may not have access to the new files (especially if the tar archive came on mag |tape from another site). GNU tar doesn't restore the original owner, unless |you are root, so it acts just like BSD's tar from the user's standpoint. | | Patrick Wolfe (pwolfe@kai.com, ...!kailand!pwolfe) | System Manager, Kuck & Associates The -o arg to the IRIX tar has a similar effect. It can be be particularly useful when restoring a tape with files in directories that are not 777, and you are not running as root, perhaps because you don't trust the tape to not have absolute paths (and do not remember -R). Vernon Schryver Silicon Graphics vjs@sgi.com
pwolfe@kailand.kai.com (Patrick Wolfe) (12/30/89)
> Written by ciemo@bananapc.wpd.sgi > > The BSD functionality of not giving away files can be accomplished with AT&T > tar by using the -o (do not chown or chgrp files). You don't need a special > tar to accomplish this. Thanks for pointing this out! BSD tar does have a "-o" option, but it does something completely different, so I guess I just didn't read the description for it on the Iris manpage. Yet another case of RTFM! Patrick Wolfe (pwolfe@kai.com, ...!kailand!pwolfe) System Manager, Kuck & Associates
ktl@wag240.caltech.edu (Kian-Tat Lim) (01/03/90)
In the referenced article, pwolfe@kailand (Patrick Wolfe) writes: >Try GNU tar. for backing up our 4D/240 over an Ethernet to a 9-track tape drive. This turns out to be an excellent solution. If anyone wants the minor fixes I needed to make to get GNU tar up and running under Irix 3.1F, send me E-mail. -- Kian-Tat Lim (ktl@wagvax.caltech.edu, KTL @ CITCHEM.BITNET, GEnie: K.LIM1)