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distribute / share volumes in docker swarm

Hi, is it possible to share docker-volumes - created with the profitbricks docker volume plugin - between docker swarm nodes? Many thanks, Uli

BTW: is it possible to share volumes (they are iscsi, aren't they) between servers?

 
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Hi Uli,

Volumes that are created with the ProfitBricks Docker volume plugin are provisioned as a new storage volume and can only be attached to one server/node at a time. They are mounted as block devices. (i.e., /dev/vdb) It is possible to unmount/detach the volume and attach it to another server/node in the same virtual data center.

As far as I know, there is no default or provided method to share volumes between servers. They can only be attached to a single server at a time.

It seems like you'd need to explore something like GlusterFS, which runs as a service on each server/node and replicates data between block storage devices attached to each node. I've only worked with it a limited amount in non-production settings, and can't really speak to how well it works with containers under load. It is something that I'd like to spend some time testing out. There are other distributed file system options out there too. Perhaps somebody else will chime in with some recommendations based on their experiences.

Eric

Hi Eric, Thanks for your answer - and - sorry for the delay. One more question: Is it possible to "attach" one Volume created with the ProfitBricks Docker volume plugin to more than one container (across swarm nodes)? Many thanks again, Uli

Hi Uli,

If I'm understanding what you are asking correctly, then the ProfitBricks Docker volume plugin does not support the use case you are describing. Since the block storage is attached and made available to a single node, only containers on that node would have access to it. Containers on other swarm nodes wouldn't see it. That being said, I haven't gotten to personally test this out to verify.

This article on medium.com is clearly biased towards StorageOS, but it discusses a number of different technologies and products that are attempting to address container storage issues.

You may find it worth your time to read if you haven't already encountered it.

Eric