Ceph using Monitor key/value store
Ceph monitors make use of leveldb to store cluster maps, users and keys. Since the store is present, Ceph developers thought about exposing this through the monitors interface. So monitors have a …
Read more →Ceph: manually repair object
Debugging scrubbing errors can be tricky and you don’t necessary know how to proceed.
Read more →Stretching Ceph networks
This is a quick note about Ceph networks, so do not expect anything lengthy here :). Usually Ceph networks are presented as cluster public and cluster private. However it is never mentioned that you …
Read more →Feel the awk power
Some of my favorite AWK expressions: OSD_LISTEN_PORTS:$(netstat -tlpn | awk -F ":" '/ceph-osd/ { sub (" .*", "", $2); print $2 }' | uniq) NETWORK=$(ip -4 -o a | awk …
Read more →Ceph: analyse journal write pattern
Simple trick to analyse the write patterns applied to your Ceph journal.
Read more →Ceph rolling upgrades with Ansible
Recently I improved a playbook that I wrote a couple of months ago regarding Ceph rolling upgrades. This playbook is part of the Ceph Ansible repository and available as rolling_update.yml …
Read more →OpenStack Summit Vancouver: thanks for your votes
Bonjour, bonjour ! Quick post to let you know that my talk submission has been accepted, so I’d like to thank you all for voting. As a reminder, our talk (Josh Durgin and I) is scheduled …
Read more →OpenStack: reserve memory on your hypervisors
One major use case for operators is to be able to reserve a certain amount of memory in the hypervisor. This is extremely useful when you have to recover from failures. Imagine that you run all your …
Read more →OpenStack Glance NFS and Compute local direct fetch
This feature has been around for quite a while now, if I remember correctly it was introduced in the Grizzly release. However, I never really got the chance to play around with it. Let’s assume …
Read more →OpenStack guest and watchdog
Libvirt has the ability to configure a watchdog device for QEMU guests. When the guest operating system hangs or crashes the watchdog device is used to automatically trigger some actions. The …
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