Re: geo-replication

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

 



Thank you for your help!
Just to make things clear to me (and get a better understanding of gluster):
So, if I make the slave cluster just distributed and node 1 goes down,
data (say file.txt) that belongs to node 1 will not be synced.
When node 1 comes back up does the master not realize that file.txt has not
been synced and makes sure that it is synced when it has contact with node 1 again?
So file.txt will not exist on node 1 at all?

I did a small test on my testing machines.
Turned one of the geo machines off and created 10000 files containing one
short string in the master nodes.
Nothing became synced with the geo slaves.
When I turned on the geo machine again all 10000 files were synced to the geo slaves.
Ofcause devided between the two machines.
Is this the right/expected behavior of geo-replication with a distributed cluster?

Many thanks in advance!

Regards
Marcus


On Wed, Feb 07, 2018 at 06:39:20PM +0530, Kotresh Hiremath Ravishankar wrote:
> We are happy to help you out. Please find the answers inline.
> 
> On Tue, Feb 6, 2018 at 4:39 PM, Marcus Pedersén <marcus.pedersen@xxxxxx>
> wrote:
> 
> > Hi all,
> >
> > I am planning my new gluster system and tested things out in
> > a bunch of virtual machines.
> > I need a bit of help to understand how geo-replication behaves.
> >
> > I have a master gluster cluster replica 2
> > (in production I will use an arbiter and replicatied/distributed)
> > and the geo cluster is distributed with 2 machines.
> > (in production I will have the geo cluster distributed)
> >
> 
> It's recommended to use slave also to be distribute replicate/aribiter/ec.
> Choosing only distribute will cause issues
> when of the slave node is down and a file is being synced which belongs to
> that node. It would not sync
> later.
> 
> 
> > Everything is up and running and creating files from client both
> > replicates and is distributed in the geo cluster.
> >
> > The thing I am wondering about is:
> > When I run: gluster volume geo-replication status
> > I see both slave nodes one is active and the other is passive.
> >
> > MASTER NODE    MASTER VOL     MASTER BRICK    SLAVE USER    SLAVE
> >                                 SLAVE NODE      STATUS     CRAWL STATUS
> >    LAST_SYNCED
> > ------------------------------------------------------------
> > ------------------------------------------------------------
> > ---------------------------------------------------
> > gluster1       interbullfs    /interbullfs    geouser
> >  ssh://geouser@gluster-geo1::interbullfs-geo    gluster-geo2    Active
> >  Changelog Crawl    2018-02-06 11:46:08
> > gluster2       interbullfs    /interbullfs    geouser
> >  ssh://geouser@gluster-geo1::interbullfs-geo    gluster-geo1    Passive
> >   N/A                N/A
> >
> >
> > If I shutdown the active slave the status changes to faulty
> > and the other one continues to be passive.
> >
> 
> > MASTER NODE    MASTER VOL     MASTER BRICK    SLAVE USER    SLAVE
> >                                 SLAVE NODE      STATUS     CRAWL STATUS
> > LAST_SYNCED
> > ------------------------------------------------------------
> > ------------------------------------------------------------
> > ----------------------------------------
> > gluster1       interbullfs    /interbullfs    geouser
> >  ssh://geouser@gluster-geo1::interbullfs-geo    N/A             Faulty
> >  N/A             N/A
> > gluster2       interbullfs    /interbullfs    geouser
> >  ssh://geouser@gluster-geo1::interbullfs-geo    gluster-geo1    Passive
> >   N/A             N/A
> >
> >
> > In my understanding I thought that if the active slave stopped
> > working the passive slave should become active and should
> > continue to replicate from master.
> >
> > Am I wrong? Is there just one active slave if it is setup as
> > a distributed system?
> >
> 
> The Active/Passive notion is for master node. If gluster1 master node is
> down  glusterd2 master node will become Active.
> It's not for slave node.
> 
> 
> 
> >
> > What I use:
> > Centos 7, gluster 3.12
> > I have followed the geo instructions:
> > http://docs.gluster.org/en/latest/Administrator%20Guide/Geo%20Replication/
> >
> > Many thanks in advance!
> >
> > Bets regards
> > Marcus
> >
> > --
> > **************************************************
> > * Marcus Pedersén                                *
> > * System administrator                           *
> > **************************************************
> > * Interbull Centre                               *
> > * ================                               *
> > * Department of Animal Breeding & Genetics — SLU *
> > * Box 7023, SE-750 07                            *
> > * Uppsala, Sweden                                *
> > **************************************************
> > * Visiting address:                              *
> > * Room 55614, Ulls väg 26, Ultuna                *
> > * Uppsala                                        *
> > * Sweden                                         *
> > *                                                *
> > * Tel: +46-(0)18-67 1962                         *
> > *                                                *
> > **************************************************
> > *     ISO 9001 Bureau Veritas No SE004561-1      *
> > **************************************************
> > _______________________________________________
> > Gluster-users mailing list
> > Gluster-users@xxxxxxxxxxx
> > http://lists.gluster.org/mailman/listinfo/gluster-users
> 
> 
> 
> 
> -- 
> Thanks and Regards,
> Kotresh H R

-- 
**************************************************
* Marcus Pedersén                                * 
* System administrator                           *
**************************************************
* Interbull Centre                               *
* ================                               *
* Department of Animal Breeding & Genetics — SLU *
* Box 7023, SE-750 07                            *
* Uppsala, Sweden                                *
**************************************************
* Visiting address:                              *
* Room 55614, Ulls väg 26, Ultuna                *
* Uppsala                                        *
* Sweden                                         *
*                                                *
* Tel: +46-(0)18-67 1962                         *
*                                                *
**************************************************
*     ISO 9001 Bureau Veritas No SE004561-1      *
**************************************************
_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://lists.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