tim@oucs.UUCP (Tim Thompson) (04/30/86)
I've been reading the discussion about the shortcomings of multiple tape
backups in cpio format. Does tar handle multiple tapes better?
I'm the SA for a PDP-11/70 running SysVr2, and currently keep two sets of
weekly backups: one in volcopy format for quick recovery of an entire file
system, and the other in cpio format to recover a single file or groups
of files. But with the problems I've read about cpio in this newsgroup,
I have a question: Would I be well-advised to switch from cpio backups
to tar backups ? Any and all comments and opinions are welcome via e-mail.
Thanks in advance.
--
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Tim Thompson 414 Morton Hall Ohio University Athens, Ohio 45701
ihnp4!{amc1,cbdkc1,cbosgd,cbrms1,cuuxb}!oucs!tim
Disclaimer: If the University finds out what I'm doing, they probably
couldn't care less.
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+greg@ncr-sd.UUCP (Greg Noel) (05/02/86)
In article <236@oucs.UUCP> tim@oucs.UUCP (Tim Thompson) writes: >I've been reading the discussion about the shortcomings of multiple tape >backups in cpio format. Does tar handle multiple tapes better? Last I looked, tar didn't handle multiple reels at all. -- -- Greg Noel, NCR Rancho Bernardo Greg@ncr-sd.UUCP or Greg@nosc.ARPA
SofPasuk@imagen.UUCP (05/04/86)
> In article <236@oucs.UUCP> tim@oucs.UUCP (Tim Thompson) writes: > >I've been reading the discussion about the shortcomings of multiple tape > >backups in cpio format. Does tar handle multiple tapes better? > > Last I looked, tar didn't handle multiple reels at all. > -- ... Depends upon the "flavor" of Eunuchs. Some SysV porters "fixed" their versions of "cpio" to handle multiple volumes of media. One good example is Convergent Technologies in CTIX ...
tanner@ki4pv.UUCP (Tanner Andrews) (05/07/86)
] Last time I looked, "tar" doesn't handle multiple In fact, if you are willing to specify the volume size in advance (either in feet & trust it, or in K), "tar" will happily close the device (rewind tape generally happens around here) and prompt you for a new volume. No standard tape labels or anything of the sort, of course. tanner andrews, systems compudata south, deland -- <std dsclm, copies upon request> Tanner Andrews
cycy@isl1.ri.cmu.edu (Christopher Young) (05/08/86)
> In article <236@oucs.UUCP> tim@oucs.UUCP (Tim Thompson) writes: > >I've been reading the discussion about the shortcomings of multiple tape > >backups in cpio format. Does tar handle multiple tapes better? > > Last I looked, tar didn't handle multiple reels at all. > -- When did you look last? I've used multiple tar with multiple tapes plenty of times. I haven't had any problems. If I were doing backups of the system, however, I'd be more inclined to use dump and restore. I can't say I'm terribly fond of cpio, however when using streaming tape on a 3b2, tar does weird things so that it takes much longer than cpio. Cpio works better in that case.
davidsen@steinmetz.UUCP (Davidsen) (05/16/86)
In article <355@imagen.UUCP> SofPasuk@imagen.UUCP writes: >> In article <236@oucs.UUCP> tim@oucs.UUCP (Tim Thompson) writes: >> >I've been reading the discussion about the shortcomings of multiple tape >> >backups in cpio format. Does tar handle multiple tapes better? >> >> Last I looked, tar didn't handle multiple reels at all. >> -- > >... Depends upon the "flavor" of Eunuchs. Some SysV porters "fixed" their >versions of "cpio" to handle multiple volumes of media. One good example >is Convergent Technologies in CTIX ... How true! Xenix/286 asks for the device name of the continuation device when cpio runs out of room on the output device (I can understand that). The AT&T 7300 tells me to press EXIT to stop or ENTER when the next disk is mounted. This implies that it is getting the device name of sysout. The Xenix method is fine if you wnat to switch between two devices to make the process go faster (assuming that you can type the device name faster than changing the media). -- -bill davidsen seismo!rochester!steinmetz!--\ / \ ihnp4! unirot ------------->---> crdos1!davidsen \ / chinet! ---------------------/ (davidsen@ge-crd.ARPA) "Stupidity, like virtue, is its own reward"
tanner@ki4pv.UUCP (Tanner Andrews) (05/19/86)
Assuming that you have a reasonable idea of the amount of data which may be placed on the disk, xenix (80286 sys3, sys5) will accept a "k" in the control keyword. This allows specificiation of the size of the output volume; you will then be prompted "tar: mount next volume" and may do the reasonable thing. This also works with using removable disks as a back-up medium. Better speed may be obtained by specifying a blocking factor which is an integral multiple of the cylinder size (or sub-multiple, if your "tar" doesn't malloc() its buffer). -- <std dsclm, copies upon request> Tanner Andrews
rick@potpourri.UUCP (09/19/86)
> > I've been reading the discussion about the shortcomings of multiple tape > backups in cpio format. Does tar handle multiple tapes better? > I'm the SA for a PDP-11/70 running SysVr2, and currently keep two sets of > weekly backups: one in volcopy format for quick recovery of an entire file > system, and the other in cpio format to recover a single file or groups > of files. But with the problems I've read about cpio in this newsgroup, > I have a question: Would I be well-advised to switch from cpio backups > to tar backups ? Any and all comments and opinions are welcome via e-mail. > Thanks in advance. > > -- > +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ > Tim Thompson 414 Morton Hall Ohio University Athens, Ohio 45701 > ihnp4!{amc1,cbdkc1,cbosgd,cbrms1,cuuxb}!oucs!tim > Disclaimer: If the University finds out what I'm doing, they probably > couldn't care less. > +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+