Add ARM architectures to Synology DSM7

[ChrisCarini]

Possibly Addresses

I think this may address #1873 & #1957 , possibly #2153 too, but unsure (not enough details in issue).

Testing

I have an example of this change published on my dockerhub account (https://hub.docker.com/repository/docker/chriscarini/zerotier-synology/general):

I've been running for ~15 days w/o any issues (according to the logs; see below):

I'd rather this be contributed back to the main project (i.e. https://github.com/zerotier/ZeroTierOne), and delete the image published to my personal DockerHub account.

Next Steps

After this PR is merged, someone w/ the respective permissions to the zerotier dockerhub would need to run the below command to get a new tag/version published out to DockerHub w/ the new architectures:

./build.sh build

CC: @joseph-henry (who I believe first added the DSM7 packaging to this repo)

[kleuter]

There's a "small" issue: DSM doesn't support installing Docker on ARM64

[ChrisCarini]

There's a "small" issue: DSM doesn't support installing Docker on ARM64

@kleuter - hmm, I'm not so sure about that.

I believe as of DSM7, DSM does support installing Docker (it's been renamed to "Container Manager") on ARM64 devices. I have a Synology DS233j (which has a Realtek RTD1619B as it's processor) and can confirm that after a fresh installation of DSM7, Container Manager is shown. Note, you can even see in the below screenshot, Container Manager's release notes shows "Added support for the following models with the ARMv8 architecture: DS220j, DS120j" (which, are older DS models, showing that the package is even supported for older hardware that is on this architecture).

p.s. Entirely up to you, of course, but it might be worth updating https://crystalidea.com/blog/zerotier-synology-arm-no-docker (one of the resources I initially found while trying to install ZeroTier on this particular device; thank you! 🎉) - bonus points (from me, of course), if you reference this PR to address the "Even if you manage to install Docker yourself (we failed), the official zerotier-synology image is amd64 only" limitation you mention. I'd love to see this PR merged in (and released to dockerhub) for exactly this reason.

[kleuter]

Thanks for the update, indeed, newer arm64 devices are supported, I updated the article mentioning your PR.

[ChrisCarini]

Cool, thank you!

Now, let's hope a maintainer of this repo takes a look at the PR, merges it in, and releases an update to dockerhub.

🙏 Bonus points if this could become part of the 'normal' release to dockerhub of all other images (though, I must admit, I didn't look to see how/where that is done or automated in this repo).