ah, so i will have to use a different tag to update an app one immediate problem i can see is that it makes garbage collecting old docker images from slaves harder : currently i update the image associated with a tag and restart tasks to update the running app, then occasionally a cron job to remove all docker images with no tag
if every updated image has a new tag it will be harder to figure out which images to remove... perhaps any with no running container, though that could lead to unnecessary pulls and slower restarts of failed tasks :craig On 5 Sep 2014, at 08:43, Ryan Thomas <[email protected]> wrote: Hey Craig, docker run will attempt a pull of the image if it cannot find a matching image and tag in its local repository. So it should only pull on the first run of a given tag. ryan On 5 Sep 2014 17:41, "mccraig mccraig" <[email protected]> wrote: > hi tim, > > if it doesn't pull on every run, when will it pull ? > > :craig > > On 5 Sep 2014, at 07:05, Tim Chen <[email protected]> wrote: > > Hi Maxime, > > It is a very valid concern and that's why I've added a patch that should > go out in 0.20.1 to not do a docker pull on every run anymore. > > Mesos will still try to docker pull when the image isn't available locally > (via docker inspect), but only once. > > The downside ofcourse is that you're not able to automatically get the > latest tagged image, but I think it's worth while price to may to gain the > benefits of not depending on registry, able to run local images and more. > > Tim > > > On Thu, Sep 4, 2014 at 10:50 PM, Maxime Brugidou < > [email protected]> wrote: > >> Hi, >> >> The current Docker integration in 0.20 does a "docker pull" from the >> registry before running any task. This means that your entire Mesos cluster >> becomes unusable if the registry goes down. >> >> The docs allow you to configure a custom .dockercfg for your tasks to >> point to a private docker registry. >> >> However it is not easy to run an HA docker registry. The docker-registry >> project recommend using S3 storage buy this is definitely not an option for >> some people. >> >> I know that for regular artifacts, Mesos can use HDFS storage and you can >> run your HDFS datanodes as Mesos tasks. >> >> So even if I attempt to have a docker registry storage in HDFS (which is >> not supported by docker-registry at the moment), I am stuck on a chicken >> and egg problem. I want to have as little services outside of Mesos as >> possible and it is hard to maintain HA services (especially outside of >> Mesos). >> >> Is there anyone running Mesos with Docker in production without S3? I am >> trying to make all the services outside of Mesos (the "infra" services that >> are necessary to run Mesos like DNS, Haproxy, Chef server... etc) either HA >> or not critical for the cluster to run. The docker registry is a new piece >> of infra outside of Mesos that is critical... >> >> Best, >> Maxime >> > >
