3 ms·

Can someone explain what I can use docker for? For example could I create a web app with docker, and send that docker image as the product? How could I update t

Can someone explain what I can use docker for? For example could I create a web app with docker, and send that docker image as the product? How could I update the image remotely when it's running somewhere out there?

ragesh 13y ago
Yes, you can create a docker image of your product and publish it to a docker registry. Your customers can then pull the image from there and fire up containers. Docker.io doesn't offer private images yet, so you may want to run your own registry [1] if you need to restrict access. Docker doesn't let you push updates to containers. I think the best you can do is to push a new image to your registry and ask your customers to pull and fire up new containers. [1] https://github.com/dotcloud/docker-registry https://github.com/dotcloud/docker-registry
newman314 13y ago
Exactly. I'm still struggling to find good use cases for containers over VMs. I get the instant on part but have yet to see a compelling use case that goes for container over VM.
- IanCal 13y ago
  I'm working on a project that has two different services running that talk to each other, a postgres and mysql database and an elasticsearch instance. Potentially both services may talk to the ES instance. With docker, I can run each of these things in a container and link them together. With a VM I'd either have a lot of VMs running or have everything on one host (and if I have everything on one host I can't just push this to production as we may want these things running on different machines). Building them is extremely quick as intermediate build results are cached, and moving them about is similarly fast as I only have to push around diffs. This isn't to say that containers are better than VMs, just that they're better for what I'm doing. > I get the instant on part but have yet to see a compelling use case that goes for container over VM. Looking at it the other way, what are the compelling reasons to go for VMs over containers? If they don't apply for your use case, then why not have something lighter and faster?

ragesh 13y ago

Yes, you can create a docker image of your product and publish it to a docker registry. Your customers can then pull the image from there and fire up containers. Docker.io doesn't offer private images yet, so you may want to run your own registry [1] if you need to restrict access. Docker doesn't let you push updates to containers. I think the best you can do is to push a new image to your registry and ask your customers to pull and fire up new containers. [1] https://github.com/dotcloud/docker-registry https://github.com/dotcloud/docker-registry

newman314 13y ago

Exactly. I'm still struggling to find good use cases for containers over VMs. I get the instant on part but have yet to see a compelling use case that goes for container over VM.

IanCal 13y ago
I'm working on a project that has two different services running that talk to each other, a postgres and mysql database and an elasticsearch instance. Potentially both services may talk to the ES instance. With docker, I can run each of these things in a container and link them together. With a VM I'd either have a lot of VMs running or have everything on one host (and if I have everything on one host I can't just push this to production as we may want these things running on different machines). Building them is extremely quick as intermediate build results are cached, and moving them about is similarly fast as I only have to push around diffs. This isn't to say that containers are better than VMs, just that they're better for what I'm doing. > I get the instant on part but have yet to see a compelling use case that goes for container over VM. Looking at it the other way, what are the compelling reasons to go for VMs over containers? If they don't apply for your use case, then why not have something lighter and faster?