[linux-lvm] LVM2 intergrated 'native' mirroring support ?

[linux-lvm] LVM2 intergrated 'native' mirroring support ?

[John Smith]

Hi.


I was wondering if current releases of LVM2 included mirroring support
in the actual logical volume manager itself ('native' mirroring
support), without the need for any other external mirroring solutions
(like for example 'dm') ?



Sincerely,


John Smith.

Re: [linux-lvm] LVM2 intergrated 'native' mirroring support ?

[Barnaby Claydon]

Hi John,

In short; No.

I believe the most common, practical method to achieve some sort of data 
protection is to have your devices in a RAID array with the LVM 
configuration on top. You're probably already aware, given that you 
mentioned 'dm', but this method means the mirroring is abstracted out 
from LVM and handled by the dedicated processes.

Sorry that wasn't a great help, but thought I'd share. I'm actually 
considering the best approach myself in preparation for rebuilding my 
file-server, and I found (oddly enough) a very informative Slashdot.org 
comment thread on the general subject:

http://ask.slashdot.org/comments.pl?sid=169386&cid=14117414

Good luck!
-Barnaby


John Smith wrote:
> Hi.
>
>
> I was wondering if current releases of LVM2 included mirroring support
> in the actual logical volume manager itself ('native' mirroring
> support), without the need for any other external mirroring solutions
> (like for example 'dm') ?
>
>
>
> Sincerely,
>
>
> John Smith.
>
> _______________________________________________
> 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/
>   

Re: [linux-lvm] LVM2 intergrated 'native' mirroring support ?

[John Smith]

On 3/6/06, Barnaby Claydon <bclaydon@volved.com> wrote:
> Hi John,
>
> In short; No.
>
Alright, but... what's all this "use lvcreate -m to create mirror
LV's" stuff I keep reading about in the mailing list about then ?
Isn't that LVM2 integrated 'native' mirroring support ?

What am I missing here ?


Sincerely,


John Smith.

Re: [linux-lvm] LVM2 intergrated 'native' mirroring support ?

[Barnaby Claydon]

Apparently there are a couple of new developments regarding the mirror 
LVs you mention.

I found some interesting details from Redhat:

http://developer.osdl.org/dev/clusters/docs/cluster_summit_mirror_paper.pdf

http://www.redhat.com/archives/linux-lvm/2005-August/msg00107.html

Still in development currently, so the functionality is somewhat limited.

Hope those help - sorry for jumping the gun James.

-Barnaby



John Smith wrote:
> On 3/6/06, Barnaby Claydon <bclaydon@volved.com> wrote:
>   
>> Hi John,
>>
>> In short; No.
>>
>>     
> Alright, but... what's all this "use lvcreate -m to create mirror
> LV's" stuff I keep reading about in the mailing list about then ?
> Isn't that LVM2 integrated 'native' mirroring support ?
>
> What am I missing here ?
>
>
> Sincerely,
>
>
> John Smith.
>
> _______________________________________________
> 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/
>   

Re: [linux-lvm] LVM2 intergrated 'native' mirroring support ?

[John Smith]

On 3/6/06, Barnaby Claydon <bclaydon@volved.com> wrote:
> Apparently there are a couple of new developments regarding the mirror
> LVs you mention.
>
> I found some interesting details from Redhat:
>
> http://developer.osdl.org/dev/clusters/docs/cluster_summit_mirror_paper.pdf
>
Ok, so if I understand correctly: LVM2 *still* requires device-mapper
but the mirroring functionality is integrated into the current CVS
version of LVM2, which not only makes LVM2 aware of the mirrors but
also removes the need for making the mirror copies 'outside' of the
logical volume manager.

Cool.


Sincerely,

John Smith.