Re: [SSI-users] Debian Lenny OpenSSI with LVM and RAID 1

[John H. <jo...@Ca...>]

Cumberland, Lonnie wrote:
> Now I am looking at the disk drives that are located on each node for mapping into a single filespace so that all space appears to be a single drive to the users. For this, I was reading that OpenSSI appears to be using DRBD (if I understand correctly) which allows it to mount the filespace on each node. If this is so then I am guessing that perhaps I could use LVM to bring all of the drives together into a volume.
>
> If that is not possible then perhaps I am utilize a stackable files system from FUSE like XtreemFS, gfs, or some other. Any ideas?
>
> I am also going to be adding RAID 1 to the system so that the main drive has a complete mirror and failover incase the main drive goes down then the secondary will pick up.
>   
Your problem with linux raid and lvm wil be making sure that things get 
failed over from node to node in the event of a node crash.

This works:

use DRDB to mirror between the nodes
use CFS to make the filesystem on the DRBD device available to all the 
nodes.

This also works:

Use shared disk hardware (SAS, SCSI, Fibre Channel, whatever) to make 
the disks available to all the nodes.
Use CFS on the disks to make the filesystem to all the nodes.

This has worked in the past, I have no practical experience:

Use a cluster aware filesystem (Lustre, even NFS) and mount the 
filesystem on all the nodes.