Hi Henry,
Thanks for your quick reply. I believe our crushmap is
updated correctly to take care of osd node failures. I
am attaching the text version of the crushmap with this
mail. Pl help us find the mistake if any.
Regards.
--ajit
On Thu, 2011-04-28 at 17:10 +0800, Henry Chang wrote:
> 2011/4/28 Ajit K Jena <[email protected]>:
> > Hi All,
> >
> > We have been experimenting with ceph since version 0.24 and
> > found one important issue that is not resolved (or may be
> > we don't know how to configure properly).
> >
> > I will talk about 0.27 since that is the latest release:
> >
> > We have a one mon, one mds, and two osd setup. The data
> > stored goes to both the osds. We introduce a third osd.
> > the ceph status shows "osd: 3 up, 3 in" but no data goes
> > into the third osd. This remains the case even if we
> > power off one of the original osds.
> >
> > Data reliability thru replication is one of the major goals
> > of ceph. I am wondering as to what we might be missing to
> > get this feature going. I am attaching the configuration
> > file.
> >
> > Pl help us solve this problem.
> >
> > Regards.
> >
> > --ajit
> >
>
> Hi Ajit,
>
> The symptom looks like the crushmap has not been updated after you
> introduced the third osd, so the data never goes into it. If that is
> the case, you may refer to the wiki page
> (http://ceph.newdream.net/wiki/OSD_cluster_expansion/contraction#Include_the_new_OSD_in_the_data_placement)
> to adjust the crushmap of your cluster.
>
> Cheers,
> --
> Henry
> --
> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
# begin crush map
# devices
device 0 device0
device 1 device1
device 2 device2
# types
type 0 device
type 1 domain
type 2 pool
# buckets
domain root {
id -1 # do not change unnecessarily
alg straw
hash 0 # rjenkins1
item device0 weight 1.000
item device1 weight 1.000
item device2 weight 1.000
}
# rules
rule data {
ruleset 0
type replicated
min_size 1
max_size 10
step take root
step choose firstn 0 type device
step emit
}
rule metadata {
ruleset 1
type replicated
min_size 1
max_size 10
step take root
step choose firstn 0 type device
step emit
}
rule casdata {
ruleset 2
type replicated
min_size 1
max_size 10
step take root
step choose firstn 0 type device
step emit
}
rule rbd {
ruleset 3
type replicated
min_size 1
max_size 10
step take root
step choose firstn 0 type device
step emit
}
# end crush map