Joseph Lorenzini
2017-Feb-26 16:19 UTC
[Gluster-users] managing lifecycle of a gluster volume in openshift
Hi all, I am happy to report that I finally got a container in an openshift pod to mount a gluster volume successfully. This has nothing to do with gluster, which works fine, and everything to do with openshift interfaces being less than ideal. Note to self: turn off the settings in openshift that prevent containers from running as root (what a silly restriction). So now I need to tackle a much more complicated problem. How to handle the lifecycle of a gluster volume in openshift.... Here are the things I am considering and I'd be interested to see how others have addressed this problem. Lets assume for the purposes of this conversation we have a single gluster cluster that will use a replicated volumes with a replica count of 3 (nothing is distributed) and the cluster consists of three nodes. So each volume minimally has three bricks, where each server only has one of the bricks. Total available disk throughput gluster is 1 terabyte. - do you use a single gluster volume for multiple pods or one gluster volume for each pod Until gluster supports mounting a subdirectory in a volume natively (can't wait for that feature!!), it seems like you'd want to go the route of volume per pod for reasons of multi-tenancy and security. - if you do a gluster volume per pod, how do you handle the physical storage that backs the gluster cluster? For example, lets say each gluster server has three devices (/dev/sdb,/dev/sdc,/dev/sdd) that can be used by bricks. Would it be a good idea to create a volume for each openshift pod, where there are multiple brick processes writing to the same device on the same disk for different volumes? Or would that have unacceptable performance implications? The reason I ask is that the gluster docs seems to recommend having physical devices dedicated to a single volume only. I did take a look at heketi but have a variety of concerns/questions on that, which are probably more appropriate for whatever email list discusses heketi. https://github.com/screeley44/openshift-docs/blob/ ce684e3c4c581db3b4aa27ecc1dba2ea65f51eda/install_config/ storage_examples/external_gluster_dynamic_example.adoc Thanks, Joe -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20170226/13cecdb0/attachment.html>