Re: [Dump-users] back up to a hard drive

[Kenneth P. <sh...@se...>]

--On Monday, April 11, 2005 11:53 AM -0700 Anthony Ewell <ae...@gb...> 
wrote:

>     CRU makes a hot swappable carrier:
>         http://www.cruinc.com/htmldocs/products/SATAdp5plus.htm
> that comes well recommended.

Looks nice. What do those cost?

I've been buying ATAPI drives and mounting them in USB2 enclosures, which 
run around $50. I've been mounting the drive to my Win2k system as NTFS, 
then sharing the partition over SMB or CIFS on gigabit Ethernet. (See my 
earlier posts for what's needed to get decent throughput.)

>     1)  as long as the backup drive is unmounted, will Linux
> freak out when the drive gets jerked out of its carrier?
>
>     2)  will Linux get annoyed at the new hard drive being
> inserted (mount /dev/hdb1)?  (It will have a new serial
> number, etc.)

Probably best to look for the kernel storage guys and see what they have to 
say. The question is how the SATA driver associates hot-swapped drives with 
/dev names. You may also need to modprobe the driver if this is the only 
SATA drive. The whole issue of how to handle hot-swapped disks is ongoing.

>     3)  would it be faster to leave compression on or off
> when doing a dump? (I will have lots of room on the backup
> drive.)

I'm using 300 GB to store two copies of my server, and because it's over 
the network, compression might improve throughput, but only if there's 
enough CPU to keep the buffers full so you don't get start-stop hiccups.

>     4)  any gotchas I am missing?  Will dump work properly with
> this scheme?

Since I'm using NTFS over Samba, I had to use the -M option to break the 
backup into many 1 GByte files. I then do a verify pass and that seems to 
go fine. "Live" files like logs and some mailboxes get reported in the 
verify, which tells me that it's working right. (It's also a good idea to 
do a "fire drill" and restore random files from the backup to insure that 
you know how to do that and that your backup files are good.)