[linux-lvm] Volume Groups and Clusters

[linux-lvm] Volume Groups and Clusters

[Joshua ChaitinPollak]

Hello, I found this mention of sharing Volume Groups across Clusters  
on the LVM howto:

http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html

Am I right in assuming that this means you can have a single volume  
group active on multiple nodes in a cluster, provided that you doing  
mount the same logical volume on more than one node at a time?

Thanks,

Josh

-- 
Joshua ChaitinPollak
Software Engineer
Kiva Systems

Re: [linux-lvm] Volume Groups and Clusters

[Heinz Mauelshagen]

On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak wrote:
> Hello, I found this mention of sharing Volume Groups across Clusters  
> on the LVM howto:
> 
> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
> 
> Am I right in assuming that this means you can have a single volume  
> group active on multiple nodes in a cluster, provided that you doing  
> mount the same logical volume on more than one node at a time?

Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
as well to be able to mount shared logical volumes on multiple nodes
at once or you mess up the data.

> 
> Thanks,
> 
> Josh
> 
> -- 
> Joshua ChaitinPollak
> Software Engineer
> Kiva Systems
> 
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

-- 

Regards,
Heinz    -- The LVM Guy --

*** Software bugs are stupid.
    Nevertheless it needs not so stupid people to solve them ***

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Heinz Mauelshagen                                 Red Hat GmbH
Consulting Development Engineer                   Am Sonnenhang 11
Cluster and Storage Development                   56242 Marienrachdorf
                                                  Germany
Mauelshagen@RedHat.com                            +49 2626 141200
                                                       FAX 924446
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Re: [linux-lvm] Volume Groups and Clusters

[Joshua ChaitinPollak]

On Feb 22, 2006, at 3:49 AM, Heinz Mauelshagen wrote:

> On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak wrote:
>> Hello, I found this mention of sharing Volume Groups across Clusters
>> on the LVM howto:
>>
>> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
>>
>> Am I right in assuming that this means you can have a single volume
>> group active on multiple nodes in a cluster, provided that you doing
>> mount the same logical volume on more than one node at a time?
>
> Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
> as well to be able to mount shared logical volumes on multiple nodes
> at once or you mess up the data.

Right, but I don't need GFS if I'm only going to mount the file  
system on one machine at a time, right?

-- 
Joshua ChaitinPollak
Software Engineer
Kiva Systems

Re: [linux-lvm] Volume Groups and Clusters

[Patrick Caulfield]

Joshua ChaitinPollak wrote:
> 
> On Feb 22, 2006, at 3:49 AM, Heinz Mauelshagen wrote:
> 
>> On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak wrote:
>>> Hello, I found this mention of sharing Volume Groups across Clusters
>>> on the LVM howto:
>>>
>>> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
>>>
>>> Am I right in assuming that this means you can have a single volume
>>> group active on multiple nodes in a cluster, provided that you doing
>>> mount the same logical volume on more than one node at a time?
>>
>> Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
>> as well to be able to mount shared logical volumes on multiple nodes
>> at once or you mess up the data.
> 
> Right, but I don't need GFS if I'm only going to mount the file system
> on one machine at a time, right?

No, just a lot of care and discipline :)

-- 

patrick

Re: [linux-lvm] Volume Groups and Clusters

[Joshua ChaitinPollak]

On Feb 22, 2006, at 8:12 AM, Patrick Caulfield wrote:

> Joshua ChaitinPollak wrote:
>>
>> On Feb 22, 2006, at 3:49 AM, Heinz Mauelshagen wrote:
>>
>>> On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak  
>>> wrote:
>>>> Hello, I found this mention of sharing Volume Groups across  
>>>> Clusters
>>>> on the LVM howto:
>>>>
>>>> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
>>>>
>>>> Am I right in assuming that this means you can have a single volume
>>>> group active on multiple nodes in a cluster, provided that you  
>>>> doing
>>>> mount the same logical volume on more than one node at a time?
>>>
>>> Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
>>> as well to be able to mount shared logical volumes on multiple nodes
>>> at once or you mess up the data.
>>
>> Right, but I don't need GFS if I'm only going to mount the file  
>> system
>> on one machine at a time, right?
>
> No, just a lot of care and discipline :)

Great! And, my co-workers keep telling me, "You lack discipline!"

-- 
Joshua ChaitinPollak
Software Engineer
Kiva Systems

Re: [linux-lvm] Volume Groups and Clusters

[Jeff Hardy]

I played around with this kind of setup for awhile, and found that there
was no need to vgchange -an on the "Other nodes" when I was making
changes on the "Admin node."  I was also able to make volume changes on
two Admin nodes at the same time.  I figured I was probably just
extremely lucky to win some extremely dangerous race conditions, so I
wouldn't do it in production.  I assume the cluster extensions to LVM
(CLVM) are what allow multiple Admin actions on multiple Admin nodes?

Anyway, just some friendly advice: follow the docs :)


On Wed, 2006-02-22 at 08:27 -0500, Joshua ChaitinPollak wrote:
> On Feb 22, 2006, at 8:12 AM, Patrick Caulfield wrote:
> 
> > Joshua ChaitinPollak wrote:
> >>
> >> On Feb 22, 2006, at 3:49 AM, Heinz Mauelshagen wrote:
> >>
> >>> On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak  
> >>> wrote:
> >>>> Hello, I found this mention of sharing Volume Groups across  
> >>>> Clusters
> >>>> on the LVM howto:
> >>>>
> >>>> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
> >>>>
> >>>> Am I right in assuming that this means you can have a single volume
> >>>> group active on multiple nodes in a cluster, provided that you  
> >>>> doing
> >>>> mount the same logical volume on more than one node at a time?
> >>>
> >>> Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
> >>> as well to be able to mount shared logical volumes on multiple nodes
> >>> at once or you mess up the data.
> >>
> >> Right, but I don't need GFS if I'm only going to mount the file  
> >> system
> >> on one machine at a time, right?
> >
> > No, just a lot of care and discipline :)
> 
> Great! And, my co-workers keep telling me, "You lack discipline!"
> 

Re: [linux-lvm] Volume Groups and Clusters

[Heinz Mauelshagen]

On Fri, Feb 24, 2006 at 02:22:08PM -0500, Jeff Hardy wrote:
> I played around with this kind of setup for awhile, and found that there
> was no need to vgchange -an on the "Other nodes" when I was making
> changes on the "Admin node."  I was also able to make volume changes on
> two Admin nodes at the same time.  I figured I was probably just
> extremely lucky to win some extremely dangerous race conditions, so I
> wouldn't do it in production.  I assume the cluster extensions to LVM
> (CLVM) are what allow multiple Admin actions on multiple Admin nodes?

Yes.

Heinz

> 
> Anyway, just some friendly advice: follow the docs :)
> 
> 
> On Wed, 2006-02-22 at 08:27 -0500, Joshua ChaitinPollak wrote:
> > On Feb 22, 2006, at 8:12 AM, Patrick Caulfield wrote:
> > 
> > > Joshua ChaitinPollak wrote:
> > >>
> > >> On Feb 22, 2006, at 3:49 AM, Heinz Mauelshagen wrote:
> > >>
> > >>> On Tue, Feb 21, 2006 at 04:22:10PM -0500, Joshua ChaitinPollak  
> > >>> wrote:
> > >>>> Hello, I found this mention of sharing Volume Groups across  
> > >>>> Clusters
> > >>>> on the LVM howto:
> > >>>>
> > >>>> http://www.tldp.org/HOWTO/LVM-HOWTO/sharinglvm1.html
> > >>>>
> > >>>> Am I right in assuming that this means you can have a single volume
> > >>>> group active on multiple nodes in a cluster, provided that you  
> > >>>> doing
> > >>>> mount the same logical volume on more than one node at a time?
> > >>>
> > >>> Yes, you assume right *but* you need a cluster filesystem (eg, GFS)
> > >>> as well to be able to mount shared logical volumes on multiple nodes
> > >>> at once or you mess up the data.
> > >>
> > >> Right, but I don't need GFS if I'm only going to mount the file  
> > >> system
> > >> on one machine at a time, right?
> > >
> > > No, just a lot of care and discipline :)
> > 
> > Great! And, my co-workers keep telling me, "You lack discipline!"
> > 
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Heinz Mauelshagen                                 Red Hat GmbH
Consulting Development Engineer                   Am Sonnenhang 11
Cluster and Storage Development                   56242 Marienrachdorf
                                                  Germany
Mauelshagen@RedHat.com                            +49 2626 141200
                                                       FAX 924446
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-