At 10:16 AM +0900 11/27/01, henry nelson wrote:
>On Mon, Nov 26, 2001 at 07:58:54PM +0700, Robert Elz wrote:
>[...]
>>  Actually, dump is perfect for this task - dump makes backups, it is the
>>  only real tool dedicated to that purpose, it is almost certainly what you
>>  should be using (rsync as suggested is another possibility, with slightly
>
>Thank you very much; this and the replies yesterday where great!
>
>While on this "backup" topic, maybe I can get your advice on an easy
>way to make backups over a lan (tcp/ip) to other machines.
>
>My situation is that practically all of my hardware is either from
>dumpsters or junkshops.  Some of my harddisks have 10% or more of the
>disk sequestered off because of bad sectors, others make funny noises.
>In addition, the disks are seldom more than 1GB in size.  I like to
>keep backups on entirely different machines, and just switch boxes if
>one should give out for any reason (and there are lots of reasons).
>
>What I've been doing is making tarballs of directories and then ftping
>them to another machine.  This is a bit clumsy, and also means you have
>to have at least enough space to temporarily make the tarball.  What I
>found convenient with Windows (I hear the booing already :) was Ipswitch's
>WS_FTP that would transfer whole directories and subdirectories.  In
>fact I liked it so much that when I still had a good Windows machine, I'd
>transfer whole directories to it and then transfer them again to another
>NetBSD machine, a kind of relay strategy.

NetBSD's ftp suppirts this natively.

>
>So the question out of all this is,
>
>WHAT'S THE BEST WAY TO RECURSIVELY TRANSFER WHOLE DIRECTORIES AND THEIR
>SUBDIRECTORIES OVER A LAN?
>
>Is it possible to do some kind of compression on the fly and then maybe even
>decompress at the other end?  Schematically, something like:
>    Machine 1                    lan               Machine 2
>% tar cf - . >> bzip2 > ftp ...............  > bzip2 -dc | tar xf -


To be honest, on the vintage of machines that you're likely to be 
using, compressing/decompressing will take longer than the transfer, 
so you wouldn't gain anything by doing it, other than longer coffee 
breaks ;-). That is a good method if you're transfrering across modem 
lines, but LAN speeds (even 10baseT) are fast enough that you would 
need a pretty fast machine doing the bzip to actually see any 
improvement.

That said, rsync is likely what you want for remote transfer with 
just changed files being copied.

HTH
Mike
-- 
Bikers don't *DO* taglines.