Matthias, These are good questions and some of them are common. I really should start an FAQ, so perhaps you’ll allow me to answer as an FAQ?
> How does Docker work on SmartOS? SmartOS is built as a purpose-specific container hypervisor at the core of Triton (formerly SmartDataCenter) in much the same way that ESX is at the core of vSphere. It’s possible to use SmartOS on its own for some very sophisticated purposes, but the full experience is best enjoyed via a full Triton implementation. The good news is that Triton, just like SmartOS, is open source. Installation instructions are in the Github repo, https://github.com/joyent/sdc, and I wrote up how I run it on Intel NUCs for my own test lab in https://www.joyent.com/blog/spin-up-a-docker-dev-test-environment-in-60-minutes-or-less. Triton runs Docker images in SmartOS zones via via https://github.com/joyent/sdc-docker/, but it doesn’t run the Docker daemon. And, as you found, the the Daemon isn’t supported inside a zone. The advantages of this approach are that each Docker container on Triton enjoys the same proven security, networking features, and bare metal performance that SmartOS zones have offered for years, with the convenience of Docker tooling and syntax. As always, however, Triton and SmartOS are open source and pull requests are welcome if you find something that can be improved. > Can I take advantage of ZFS for container backups? I think you’ll find a number of people on this list and in sdc-discuss that are doing container backups via ZFS that fully meet your needs, but I’ve personally enjoyed the ability to ZFS send/receive datasets between containers. > Does Triton have some kind of dynamic DNS service which I could point to a > container? We’re actively developing https://github.com/joyent/triton-cns to provide DNS in Triton as described by https://github.com/joyent/rfd/blob/master/rfd/0001/README.md. > How do I handle data-volumes in Docker on Triton? Triton supports sharing volumes among containers using `--volumes-from` syntax. That allows you to put data in one container and run the application in another. Triton does _not_ support mounting volumes from the host using the `-v` syntax, as that would violate the strong security isolation that’s required for running containers on multi-tenant bare metal. Additional details about Docker volume support can be found in https://apidocs.joyent.com/docker/features/volumes, and you can watch https://github.com/joyent/rfd for upcoming work on supporting named Docker volumes as was introduced in Docker 1.8. As always, however, Triton and SmartOS are open source and pull requests are welcome if you find something that can be improved. Thank you for these great questions, Matthias, and for giving me an opportunity to develop FAQ materials for them. —Casey > On Jan 21, 2016, at 4:16 AM, Matthias Götzke <[email protected]> wrote: > > Note: Sorry for potentially reposting, but I am experiencing issues with the > smartos-discuss list. While the previous mail did appear in the > https://www.listbox.com/member/archive/184463/=now > <https://www.listbox.com/member/archive/184463/=now> webinterface my > colleagues and I didn’t get the mail ourselves so I would assume nobody got > them via mail. This is happening quit lot recently and I haven’t nailed down > why yet. > -------------------------------------------------------------- > > > Can anybody shed some light on these Docker questions we are facing in > relation to Smartos and Triton (we are also just learning how to apply > Docker to our existing dev workflows as some questions might betray 😊 ) ? It > is our understanding that SmartOS really wants to work well with Docker but > we cannot yet see a clear path ahead as to how to actually use it without > using KVMs again or running on directly on linux and thus loosing ZFS. > > Questions: > > 1) Are there any plans on supporting docker daemon in a smartos/lx zone > in the future ? > (Right now we get errors such as ‘overlay’ not found as a supported > filesystem on this host) > 2) I see how I can use > https://github.com/joyent/smartos-live/tree/master/src/dockerinit > <https://github.com/joyent/smartos-live/tree/master/src/dockerinit> to start > a process but what exactly makes this docker ? How can I push a container > there or talk to it from my dev machine etc ? > 3) Getting started in Triton with containers was quite simple (after > understanding some limitations such as port mapping missing, not a big deal > but many examples in docker use that and thus you stumble here at first), but > how do I get snapshots made in Triton a’la zsnapper. Can I make a snapshot > copy of a container to test a configuration change ? > 4) Can I somehow zfs diff backup a container in Triton as is , to ensure > a perfect replica ? > 5) Does Triton have some kind of dynamic DNS service which I could point > to a container ? > 6) How do I handle data-volumes on Triton if Joyent doesn’t like > volume-from and there is not real ‘host’ (BrianC talked about no liking > that). Our Server Data Core Code is a web-service which has its shard of data > (append only file structure) collocated with it right now. In Docker we > would use data volumes but I don’t want to go over the network from the code > to the data. The whole point of our setup was to keep code and data together. > > Any help or pointers would be greatly appreciated. I hope there are at least > some people here how are interested in Docker on SmartOS 😉 or have more > experience with it. > > Thanks, > Matthias > > Background: > > I am experimenting with docker on sdc as well as docker directly on our > smartos hosts but are having a number of questions. > > We are currently hosting a number of smartos servers in datacenters in > Germany and some directly inside customers DCs. Right now we have a pretty > well working setup with SmartOS zones preconfigured by Chef directly from Git > on our master servers and then we can transport those as imgadm Images to our > customer or the other DC sites. Automatic Snapshotting is performed by > zsnapper and Backup is done via zfs send -I to the dedicated backup machines. > We can quickly spin up any backuped up machine somewhere else if we needed to, > > In the future though, we are looking at moving our software application to > docker to streamline some processes there and docker/smartos looked like a > great thing (also in case one of our applications would have to be moved to > an actual cloud provider such as Joyent ‘Triton’). But the amount of > available documentation on getting docker to replace our current setup is a > little elusive. > > > PS: > We do not currently have plans to setup a full SDC (mostly because we cannot > appropriately judge how much know-how we will have to build up and how long > that would take as well as the fact that 1) we don’t have head nodes setup in > the datacenter, thus new hardware would be required and 2) the SDC UI isn’t > open source it seems and 3) the whole backup/zfs management of sdc is > unclear). I am not unwilling but no matter how easy it is, it will be more > complicated and thus more to learn than just learning how to running docker > host in a vm, knowledge we would have to gain,retain and update regularily > > > > Sent from Mail <http://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 > > smartos-discuss | Archives > <https://www.listbox.com/member/archive/184463/=now> > <https://www.listbox.com/member/archive/rss/184463/26887334-6cdbd07c> | > Modify <https://www.listbox.com/member/?&;> Your Subscription > <http://www.listbox.com/> ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
