PS6000, Debian, Open-iscsi questions

My set up is as follows:

2 PS6000XV's, a primary and a secondary.

Primary has 2 volumes:

- ntfs serving mssql from Windows Server 2008 R2/SQL Server 2008 64-bit, 166GB data

- ext3, serving mysql from Debian 5/MySQL 64-bit, 55 GB data

The Windows side is fairly well integrated...

On the Debian side, I'm using open-iscsi for the iscsi initiator.

After I log into the iscsi target with multipath, I get 4 new devices, one each for the 4 san ethernet ports:

/dev/sdb, /dev/sdc, /dev/sdd, and /dev/sde

and

the /dev/mapper directory looks like this:

crw-rw---- 1 root root  10, 60 2010-03-24 20:52 control
brw-rw---- 1 root disk 254,  0 2010-03-25 09:06 mysql_san
brw-rw---- 1 root disk 254,  1 2010-03-25 09:06 mysql_san-part1

My config file for multipath has an alias for mysql_san, but not for mysql_san-part1.

I tried to format /dev/mapper/mysql_san and the os says the device is busy.

I succeeded in formating mysql_san-part1... the documentation I have says that only the alias should show up in /dev/mapper (ie /dev/mapper/mysql_san)

Is this correct?

Also, right after I formatted /dev/mapper/mysql_san-part1, the associated volume in the Group Admin software shows 33.43 GB "in use utilization" without any data in the partition.  Is the PS6000 seeing the formatting as change in the volume?

 

Any input is appreciated

Richard