[comp.unix] Does anyone have a tar or cpio that will use remote devices?

fredrick@acdpyr.ucar.edu (Tim Fredrick) (01/04/90)

[Moderators Note:-  One thing I use quite a bit, on TCP/ip systems, which
 don't have NFS, is the following:-
	tar cvf - files | rcmd user@machine dd of=device bs=10k
 It works just fine for me (on a System V machine).	- Der]

On our SPARCstations, dump is capable of remote-mounting a tape drive on
another machine by using the option "f user@machine:device".

Does anyone out there have a version of cpio or tar that will also remote-
mount a device on another machine, preferably using a similar "user@machine"
syntax?  We wish to access a high-speed tape drive for backups from remote
UNIX machines, and our cpio and tar do not support remote devices.

Thanks in advance.  --Tim
Tim Fredrick             National Center for Atmospheric Research
(303) 497-1498           Atmospheric Chemistry Division
fredrick@ncar.ucar.edu   PO Box 3000
fredrick@ncar.CSNET      Boulder, CO 80307

steve@nuchat.UUCP (Steve Nuchia) (02/23/90)

In article <3535@zorba.Tynan.COM> mvadh@cbnews.ATT.COM (andrew.d.hay,54242,wi,1d007,508 374 5484) writes:
>just a note -- sV RFS allows one to remote-mount the entire /dev directory...

What happens if the kernels are different?  Is there any protection
against, say, /dev/lp having world read/write and major/minor numbers
corresponding to /dev/mem?   Presumably one would not do this intentionally
but it strikes me as a likely kind of thing to happen as configurations
drift over time.

Is there a mechanism to protect against this sort of thing or is it
a matter of policy?
-- 
Steve Nuchia	      South Coast Computing Services      (713) 964-2462
"If the conjecture `You would rather I had not disturbed you
 by sending you this.' is correct, you may add it to the list of
 uncomfortable truths."   - Edsgar Dijkstra

ted@welch.jhu.edu (Ted Ying) (02/23/90)

>In article <3534@zorba.Tynan.COM> uunet!acdpyr.ucar.edu!fredrick (Tim Fredrick) writes:
>[]
>"On our SPARCstations, dump is capable of remote-mounting a tape drive on
>"another machine by using the option "f user@machine:device".
>"
>"Does anyone out there have a version of cpio or tar that will also remote-
>"mount a device on another machine, preferably using a similar "user@machine"
>"syntax?
>
	pdtar which is available by anonymous login from uunet.uu.net
	works exactly like tar with an additional feature.  It allows you
	to specify remote devices using the "-f host:/dev/devname" option.

	Ted Ying			ted@welchlab.welch.jhu.edu

	SEMINARS: From 'semi' and 'arse', hence, any half-assed discussion.
	Disclaimer: You don't really think this place would let me speak for
		    them do you?

guy@auspex.UUCP (Guy Harris) (03/08/90)

>>just a note -- sV RFS allows one to remote-mount the entire /dev directory...
>
>What happens if the kernels are different?  Is there any protection
>against, say, /dev/lp having world read/write and major/minor numbers
>corresponding to /dev/mem?

No, but there doesn't have to be.  If you mount a "/dev" directory from
another machine, all accesses to devices in that directory go over the
wire and access the remote machine's devices, using the *remote*
machine's interpretation of the major and minor numbers.  So, even if
"/dev/lp" on the remote machine had the same major/minor as "/dev/mem"
on your machine, using "/mnt/dev/lp" or whatever would refer to the
printer on the remote machine, not physical memory on your machine.

mark@DRD.Com (Mark Lawrence) (04/13/90)

uunet!welchlab.welch.jhu.edu!ted (Ted Ying) wrote:
}   pdtar which is available by anonymous login from uunet.uu.net
}   works exactly like tar with an additional feature.  It allows you
}   to specify remote devices using the "-f host:/dev/devname" option.

I don't know if they're the same, but Gnu tar also supports the same
syntax.  Available at finer anonymous ftp and uucp sites everywhere...

-- 
 mark@DRD.Com {uunet,rutgers}!drd!mark (918)743-3013