A common recommendation is to store OSD journal on a SSD drive which implies loosing your OSD if this journal fails.
This article assumes that your OSDs have been originally deployed with ceph-disk.
You will also realise that it’s really simple to bring your OSDs back to life after replacing your faulty SSD with a new one.
Ceph, to work in optimal circumstances requires the usage of RAW images. However, it is painful to upload RAW images in Glance because it takes a while. Let see how we can make our life easier.
The OpenStack documentation often recommends to enable the Glance cache while using the default store file, with the Ceph RBD backend things are slightly different.
Since Juno, it is not possible anymore for an user to create public images nor make one of his images/snapshots public. Even though this new Glance policy is a good initiative, let’s see how we can get the old behavior back.
During some strange circonstances, the levelDB monitor store can start taking up a substancial amount of space. Let quickly see how we can workaround that.
The next OpenStack summit is just around the corner and as usual Josh Durgin and I will lead the Ceph and OpenStack design session. This session is scheduled for November 3 from 11:40 to 13:10, find the description link here. The etherpad is already available here so don’t hesitate to add your name to the list along with your main subject of interest. See you in Paris!
This second edition of the CephDay London looks really promising. You should definitely look at the agenda! Talks go from OpenStack to deep performance studies and crossing CephFS news!
Check this out on the Eventbrite page.
I hope to see you there! I don’t have any talks, at least for once I’ll be watching :-).
A simple benchmark job to determine if your SSD is suitable to act as a journal device for your OSDs.
Almost two years ago, I was writing the results of the experiments with Flashcache. Today this blog post is a featured post, this howto was written by Andrei Mikhailovsky. Thanks for his contribution to this blog :-).
My slides from the CephDays in Paris. Main topics were: Status of Ceph in OpenStack (Juno cycle) Deploy Ceph with Ansible Video: Slide: