Fixing ceph partition uuid or OSD data dir is not mounted

Posted on Mon 06 February 2017 in Ceph • Tagged with ceph, linux, notepad, work • 1 min read

OSD_UUID

4fbd7e29-9d25-41b8-afd0-062c0ceff05d

JOURNAL_UUID

45b0969e-9b03-4f30-b4c6-b4b80ceff106

To fix the partition uuid

sgdisk --info=##partnr## -t ##partnr##:##part-uuid## /dev/##disk##

eg.
sgdisk --info=1 -t 1:4fbd7e29-9d25-41b8-afd0-062c0ceff05d /dev/sda1

Ref: /lib/udev/rules.d/95-ceph-osd.rules


Openstack Manila with CephFS as backend [notepad]

Posted on Thu 22 December 2016 in openstack • Tagged with ceph, Openstack, linux, notepad, work • 1 min read

openstack-manila-cephfs


[notepad] ceph journal size/ssd speed

Posted on Tue 18 October 2016 in Linux • Tagged with ceph, journal, ssd • 1 min read

ceph journal size (doc)

not for bluestore

osd journal size = {2 * (expected throughput * filestore max sync interval)}

The default for filestore max sync interval is 5 therefore for a 10Gbit network the "perfect" size would be

osd journal size = { 2 * ( 1280 * 5 ) } = 12.5 GB

ceph ssd speed

The optimum …


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ceph - setting up rbd-mirror between two ceph clusters

Posted on Sat 15 October 2016 in Ceph • Tagged with ceph, rbdmirror, howto, linux, notepad, work • 3 min read

Environment
2x ceph cluster (aio) running centos 7.2 /w ceph jewel. Added a 2nd crush rule to both clusters:

rule rep_osd {
    ruleset 1
    type replicated
    min_size 1
    max_size 10
    step take default
    step choose firstn 0 type osd
    step emit
}

(ceph crush map)

Setup

Install the rbd-mirror package in …


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entropy inside a virtual machine

Posted on Thu 30 June 2016 in Linux • Tagged with ceph, kvm, linux, notepad • 1 min read

Sometimes my ceph-(test!)deployments inside a VM failed.

The Problem is that the kernel/cpu can not provide enough entropy (random numbers) for the ceph-create-keys command - so it stuck/hang. It is not a ceph problem! This can also happen with ssl commands.

But first things first - we need …


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