topic Re: Sharing a logical drive between 2 servers in MSA Storage

Sharing a logical drive between 2 servers

kerpow — Tue, 13 Mar 2007 12:06:43 GMT

I have a 2TB logical drive on an MSA-30. It is currently attached to an ML-370. If possible, I would like to attach this logical drvie to another, identical server. What is the easiest (read cheapest) way of doing this? Is it possible to use some kind of Y shaped cable or will I need a controller to achieve this?

Re: Sharing a logical drive between 2 servers

Uwe Zessin — Tue, 13 Mar 2007 12:35:43 GMT

Watch out! Most operating systems / file systems do NOT support shared access to a single file system. Simple spoken: it is necessary that all servers that access a single file system 'talk to each other' and notify others about changes.

If people play with this, e.g. on Windows, they find out that _some_ things seem to work, but then problems show up like: a file creation does not show up on the other server. In the long term they will find out that their file system became corrupted.

The usual way is:
- put the disks in a SAN (FC or iSCSI)
-- but this gives only block access

- choose an operating system/ file system combination that provides concurrent access to the file system.

Re: Sharing a logical drive between 2 servers

Ivan Ferreira — Tue, 13 Mar 2007 15:10:42 GMT

What are your operating systems? You can't present the same lun for shared access unless you use a shared file system, like Red Hat GFS, Veritas Storage Foundation, Oracle OCFS 2.

You can use the lun on one server at a time. That is write the data on one server, unpresent the lun to this server, present to the other, and read or write data to the lun.

Re: Sharing a logical drive between 2 servers

kerpow — Wed, 14 Mar 2007 03:10:51 GMT

It is just a Windows 2003 box. Is there any kind of small business device that I can put between the servers and the enclosure to allow both servers to read/write the logical drive?

Thanks