I just wanted to give a friendly reminder for this issue. I would appreciate if someone
can help me out here. Also, please do let me know in case some more information is
required here.
Hi Peter,
Thanks a lot for the reply. Please find 'ceph osd df' output here -
# ceph osd df
ID WEIGHT REWEIGHT SIZE USE AVAIL %USE VAR PGS
2 0.04399 1.00000 46056M 35576k 46021M 0.08 0.00 0
1 0.04399 1.00000 46056M 40148k 46017M 0.09 0.00 384
0 0.04399 1.00000 46056M 43851M 2205M 95.21 2.99 192
0 0.04399 1.00000 46056M 43851M 2205M 95.21 2.99 192
1 0.04399 1.00000 46056M 40148k 46017M 0.09 0.00 384
2 0.04399 1.00000 46056M 35576k 46021M 0.08 0.00 0
TOTAL 134G 43925M 94244M 31.79
MIN/MAX VAR: 0.00/2.99 STDDEV: 44.85
I setup this cluster by manipulating CRUSH map using CLI. I had a default root
before but it gave me an impression that since every rack is under a single
root bucket its marking entire cluster down in case one of the osd is 95% full. So I
removed root bucket but that still did not help me. No crush rule is referring
to root bucket in the above mentioned case.
Yes, I added one osd under two racks by linking host bucket from one rack to another
using following command -
"osd crush link <name> <args> [<args>...] : link existing entry for <name> under location <args>"--On Thu, Aug 10, 2017 at 1:40 PM, Peter Maloney <peter.maloney@brockmann-consult.de > wrote:I think a `ceph osd df` would be useful.
And how did you set up such a cluster? I don't see a root, and you have each osd in there more than once...is that even possible?
On 08/10/17 08:46, Mandar Naik wrote:
Hi,
I am evaluating ceph cluster for a solution where ceph could be used for provisioning
pools which could be either stored local to a node or replicated across a cluster. This
way ceph could be used as single point of solution for writing both local as well as replicated
data. Local storage helps avoid possible storage cost that comes with replication factor of more
than one and also provide availability as long as the data host is alive.
So I tried an experiment with Ceph cluster where there is one crush rule which replicates data across
nodes and other one only points to a crush bucket that has local ceph osd. Cluster configuration
is pasted below.
Here I observed that if one of the disk is full (95%) entire cluster goes into error state and stops
accepting new writes from/to other nodes. So ceph cluster became unusable even though it’s only
32% full. The writes are blocked even for pools which are not touching the full osd.
I have tried playing around crush hierarchy but it did not help. So is it possible to store data in the above
manner with Ceph ? If yes could we get cluster state in usable state after one of the node is full ?
# ceph df
GLOBAL:
SIZE AVAIL RAW USED %RAW USED
134G 94247M 43922M 31.79
# ceph –s
cluster ba658a02-757d-4e3c-7fb3-dc4bf9
44322f health HEALTH_ERR
1 full osd(s)
full,sortbitwise,re
quire_jewel_osds flag(s) set monmap e3: 3 mons at {ip-10-0-9-122=10.0.9.122:6789
/0,ip-10-0-9-146=10.0.9.146: }6789/0,ip-10-0-9-210=10.0.9. 210:6789/0 election epoch 14, quorum 0,1,2 ip-10-0-9-122,ip-10-0-9-146,ip
-10-0-9-210 osdmap e93: 3 osds: 3 up, 3 in
flags full,sortbitwise,require_jewel
_osds pgmap v630: 384 pgs, 6 pools, 43772 MB data, 18640 objects
43922 MB used, 94247 MB / 134 GB avail
384 active+clean
# ceph osd tree
ID WEIGHT TYPE NAME UP/DOWN REWEIGHT PRIMARY-AFFINITY
-9 0.04399 rack ip-10-0-9-146-rack
-8 0.04399 host ip-10-0-9-146
2 0.04399 osd.2 up 1.00000 1.00000
-7 0.04399 rack ip-10-0-9-210-rack
-6 0.04399 host ip-10-0-9-210
1 0.04399 osd.1 up 1.00000 1.00000
-5 0.04399 rack ip-10-0-9-122-rack
-3 0.04399 host ip-10-0-9-122
0 0.04399 osd.0 up 1.00000 1.00000
-4 0.13197 rack rep-rack
-3 0.04399 host ip-10-0-9-122
0 0.04399 osd.0 up 1.00000 1.00000
-6 0.04399 host ip-10-0-9-210
1 0.04399 osd.1 up 1.00000 1.00000
-8 0.04399 host ip-10-0-9-146
2 0.04399 osd.2 up 1.00000 1.00000
# ceph osd crush rule list
[
"rep_ruleset",
"ip-10-0-9-122_ruleset",
"ip-10-0-9-210_ruleset",
"ip-10-0-9-146_ruleset"
]
# ceph osd crush rule dump rep_ruleset
{
"rule_id": 0,
"rule_name": "rep_ruleset",
"ruleset": 0,
"type": 1,
"min_size": 1,
"max_size": 10,
"steps": [
{
"op": "take",
"item": -4,
"item_name": "rep-rack"
},
{
"op": "chooseleaf_firstn",
"num": 0,
"type": "host"
},
{
"op": "emit"
}
]
}
# ceph osd crush rule dump ip-10-0-9-122_ruleset
{
"rule_id": 1,
"rule_name": "ip-10-0-9-122_ruleset",
"ruleset": 1,
"type": 1,
"min_size": 1,
"max_size": 10,
"steps": [
{
"op": "take",
"item": -5,
"item_name": "ip-10-0-9-122-rack"
},
{
"op": "chooseleaf_firstn",
"num": 0,
"type": "host"
},
{
"op": "emit"
}
]
}
--
Thanks,Mandar Naik.
_______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo .cgi/ceph-users-ceph.com
-- -------------------------------------------- Peter Maloney Brockmann Consult Max-Planck-Str. 2 21502 Geesthacht Germany Tel: +49 4152 889 300 Fax: +49 4152 889 333 E-mail: peter.maloney@brockmann-consul t.de Internet: http://www.brockmann-consult.de -------------------------------------------- Thanks,Mandar Naik.
--
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