Re: HA replica

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 02/18/2016 11:33 AM, Mike Stump wrote:
On Feb 13, 2016, at 6:21 PM, Ravishankar N <ravishankar@xxxxxxxxxx> wrote:
About the docs, could you list the links for client and server quorum where you found the details to be inadequate? I can't seem to find anything myself on readthedocs.:(
I'm anyway planning to do a detailed write up for arbiter volumes, split-brains, client and server quorums which can serve as a ready reckoner.
Hi,
So I've made a write-up here: http://gluster.readthedocs.org/en/latest/Administrator%20Guide/arbiter-volumes-and-quorum/
Hope this is more explanatory.
Thanks,
Ravi

So, http://www.gluster.org/community/documentation/index.php/GlusterFS_Concepts can explain that replica 2 is unlike RAID-1.  It can state that to achieve RAID-1, one must use replica 3.  http://gluster.readthedocs.org/en/latest/Administrator%20Guide/Setting%20Up%20Volumes/ likewise talks about high availability and replicated, but it could explain that replica 3 is required to achieve RAID-1.

In

   http://gluster.readthedocs.org/en/release-3.7.0/Features/server-quorum/

it states:

Therefore, it is highly advisable to ensure that the cluster size is three or greater.
So, I would have an easier time understanding this, is cluster size was linked to a definition.  Would my reading be correct if I read this as replica 3 or greater?

It need only be present to preserve the notion of a quorum majority less than the entire cluster membership, allowing the cluster to survive the loss of a single node without losing quorum.
Again, here it talks about cluster membership.  I think I incorrectly viewed this as relating to the total list of peers rather than the replica count.


1 - https://en.wikipedia.org/wiki/Standard_RAID_levels
2 - https://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices



_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://www.gluster.org/mailman/listinfo/gluster-users



[Index of Archives]     [Gluster Development]     [Linux Filesytems Development]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux