[Ocfs2-users] OCFS2 and LVM2

[Gerry Reno]

Alexei_Roudnev wrote:
> You must understand how LVM2 works. It is all STATIC system, so it ALWAYS
> can be used in cluster until you don't change metadata. Think about LVM as
> about partitions on the disk - you can use partitions with OCFS, so you can
> use LVM with OCFS (but you can't change partitions online).
>
> You can create LVM2 volumes using one node, then restart other nodes (and
> let them to scan disks) and they will see these volume(s). Then you can use
> it as you wish.
> But to change volumes, you will:
> - stop all nodes but one
> - update LVM2 volume on this node
> - start other nodes
>
> So, you CAN use LVM2 but you CAN NOT change metadata online while cluster
> have more than 1 running node (running node - running OS, stopping OCFS is
> not enough).
>
> PS. You don't need to create volumes on a few nodes. What you must do is to
> create volumes on ONE node and run vgscan or (boot.lvm start) on all other
> nods (so they recognize your volumes).
>   
Ok, this is a little better than I thought having to make the LVM2 
changes on just one node.  So you are saying I must shutdown the other 
nodes completely not just stop OCFS2?  That is going to require console 
access to each machine.  Could I just put them in another init level? 
Something that we could do remotely.

> I recommend to look onto EVMS integrated with OCFSv2 (by SuSe), as a
> possible alternative.
>
>   
I will look at this.

Thanks,
Gerry