Re: One time deal: Backup of raid5 to set of removeable hard drives on another machine?

[Ugo Bellavance <ugob@camo-route.com>]

Mitchell Laks wrote:
> Hi,
> 
> I have a (remotely stationed) server with a raid5 with about 630 GB of data 
> that I would like to backup to a set of  removeable hard drives on another  
> pc at the same location. 
> 
> I will use 250GB hard drives as removeables. Based upon experimentation with 
> data I find that using tar zcvf I will get the size of the data stored to 
> about 330GB of storage.
> 
> the removeable drive is mounted on /mnt/backup at 192.168.0.1. 
> 
> So I thought to do
> 
> tar zcf - directory|ssh backmeup@192.168.0.1 "cat >/mnt/backup/backup.tgz"
> 
> but that would be too big for the destination drive.
> 
> I thought of trying to use split at the destination side, but
> 
>  tar zcf - directory|ssh backmeup@192.168.0.1 "split -b \ 
> 230000m    /mnt/backup/backup"
> 
> but this wouldnt work either.
> while this would appropriately split the target into 2 files, it would still 
> run out of space and would not enable me to umount and remount the hard 
> drive...
> 
> then maybe something like 
> tar zcf - directory| split -b 23000m  | ssh backmeup@192.168.0.1 " cat 
> 
>>/mnt/backup/backup"
> 
> 
> but that doesnt work
> 
> Is there a cool unix tool (or an idea for a perl script)  to use combined with 
> split on the server side, that will then pause after split finishes creating 
> the first file so that I can umount the first drive remotely and mount the  
> second drive to receive the rest of the data?
> 
> I guess I could replace/recreate split on the server side 
> as a perl script which would count the data as it sent it and stop sending 
> when it got to 220G or so and then I could write a second script that would 
> throw away the first 220Gb and start from there.
> 
> my $buff;
> for (my $count = 0; $count < 220000000; $count++)  {
> while (read(STDIN, $buff, 1024) {
> print STDOUT , $buff;
> }
> }
> 
> I suppose I could calculate in advance a split of the directory into 2 roughly 
> equal parts, but that would be less fun than having a way of splitting and 
> then pausing...
> 
> Is there a better way?

If I understand correctly, the problem is that you have 2 removeable
drives and you can't mount them both at the same time, and one isn't
sufficient to contain all the data right?

> 
> Mitchell
> 
> 
> 
>