[CentOS] iSCSI, windows, & local linux access

Fri Feb 23 15:59:06 UTC 2007
Andrew Cotter <andrew.cotter at somersetcapital.com>

> Yes, it will be an NTFS partition, but with the "plus" kernel you can
> use the read-only ntfs module to read the data on the Linux side, just
> take an LVM snapshot, use the loopback with the sector offset of the
> partition in the snapshot lv to mount it locally. Remove the snapshot
> when done.

Does the snapshot take utilize the same amount of space?  If I have 3TB of
files, do a snapshot, do I then have 6TB of data on disk?

A little more background....

Why we are doing this is we are (re)building our array to store our
disk-disk backups using BackupExec.  The older versions did no mind using a
smb share but since we have updated to 10d it will not connect and
Symantec/Veritas does not support this.  That is why we thought iSCSI would
do the trick.

> You can't rsync NTFS partitions, but you could use drbd and scheduled
> replication to block-level replicate it. Use drbd without heartbeat,
> have it sync up asynchronously using Prot A, once it is sync'd have it
> disconnect and run standalone with secondary in wait-for-connect, using
> 'cron' bring up the connection again, when it is sync'd bring it down
> again.

Where rysnc came in for us was we then take some of those backups and spool
them off over a VPN to a remote site.  In addition, we would take a SATA
drive, mount it, copy some data, pull it, then take it offsite like people
traditionally do with tape.  I have read a bit about drdb and that might
work.  We would have to be selective somehow since we have a smaller array
at the other end meant to only hold 2wks of backups.

We used to do this with a 1TB array and smb but our data has grown fairly
rapidly.

Would something like NFS possibly suit us better?

Thanks for the suggestions!

Andrew