[Linux-cluster] Re: Linux-cluster Digest, Preventing LVM from concurrent access

[Edson Marquezani Filho]

>
> Sorry I cant validate it, my lab is not available now. I took a look at
> it and there are some points you must change:
>
> 1.- lvm-cluster resource definition: the arguments vg_name and lv_name
> are mandatory. You must activate a logical volume into the volume group.
> As far as i know, you cant build the filesystem on top of the volume
> group directly, and I built the script with some checks to avoid that.

When I said validate, I meant just check it out. I didn't expect you
to run it. Probabily it was not the appropiat word to say what I
wanted. (I'm sorry for this poor english.)

> 2.- Filesystem resource: you need to mount the filesystem stored into
> the logical volume you activate. You need a filesystem to store the VMs,
> don't you? Or do you use a "raw device" in your Xen service?

No, I don't and can't do that. LVs are passed directly to VMs'
configuration files, and Xen takes care of it. Actualy, each LV is
seen like a phisical disk by the VM. It's Xen that access and "mounts"
it.

> I updated your pastebin file. I'm not sure if it will be fully
> funcional.
>
> Maybe you should even nest the resources building your service to be
> sure they are started in order. It will depend on your service. Check my
> example.

Hum... so nesting indicates order. It's good to know. =)

>
> Yes, but if you have a management console for your VM service you will
> need a Virtual IP which "floats" with the service, so you can always
> connect to the same IP to check the status of your virtualization
> service. You can make that attaching a IP resource to your service.
>

What are the changes that needs to be done to lvm.conf, as advised in
the script code?

I have seen that there is already a resource called vm. Maybe,
lvm-cluster and vm resouces can do everything I need. I hope that it
can. =)