Using MIAB On ARM

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1

I know that ARM is officially unsupported (I see the warning on every update) but I nonetheless use it, mostly because I have a free t4g.small instance from AWS and host my MIAB on there.

I have been receiving backup errors for some time now and have ignored them.

`GPGError: GPG Failed, see log below:
===== Begin GnuPG log =====
gpg: Note: ‘–force-mdc’ is not considered an option
gpg: Note: ‘–symmetric’ is not considered an option
gpg: WARNING: no command supplied. Trying to guess what you mean …
usage: gpg [options] [filename]
===== End GnuPG log =====

Traceback (most recent call last):
File “/home/ubuntu/mailinabox/management/backup.py”, line 647, in
perform_backup(full_backup)
File “/home/ubuntu/mailinabox/management/backup.py”, line 318, in perform_backup
shell(‘check_call’, [
File “/home/ubuntu/mailinabox/management/utils.py”, line 126, in shell
ret = getattr(subprocess, method)(cmd_args, **kwargs)
File “/usr/lib/python3.10/subprocess.py”, line 369, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command ‘[’/usr/bin/duplicity’, ‘full’, ‘–verbosity’, ‘warning’, ‘–no-print-statistics’, ‘–archive-dir’, ‘/home/user-data/backup/cache’, ‘–exclude’, ‘/home/user-data/backup’, ‘–volsize’, ‘250’, ‘–gpg-options’, “‘–cipher-algo=AES256’”, ‘–allow-source-mismatch’, ‘/home/user-data’, ‘file:///home/user-data/backup/encrypted’]’ returned non-zero exit status 31.`

I decided to dive into the issue.

It seems that Duplicity for ARM is only available through version 0.8.21 (duplicity : arm64 : Jammy (22.04) : Ubuntu) which had a bug in it and was causing my GPG errors. (Backup script failing

Snap, however, has newer versions of duplicity that work on ARM.

I removed tha apt version of duplicity and installed the snap version.

However when installing via snap the MIAB scripts did not find duplicity because it was installed in /snap/bin instead of /usr/bin

To fix this I created symlink sudo ln -s /snap/bin/duplicity /bin/duplicity which then allowed the snap version of duplicity to be called by the MIAB scripts which reference /usr/bin/

Let me know if this is unclear or if you have any follow up questions.

Thanks to @dms and @KiekerJan for helping me work through this

4 Likes
2

Hi, and thanks for posting a solution to this issue. I am running MIAB on Arm (Ubuntu 22).
Please post a step by step guide including the removal of the apt version and installation of the snap.

Please help because I am not that good at the command line.

Thanks @ jacobrosenfeld

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I will reply it for myself: this is what i did:

sudo apt-get remove --purge duplicity
sudo snap install duplicity --classic --edge
sudo ln -s /snap/bin/duplicity /bin/duplicitty

I waited for the nightly reports and no error message arrived. The script is working you can check the admin backups section of your box.

Thanks again @ jacobrosenfeld

4

I use mailinabox on ARM, because I use Hetzner ARM servers, which are cheaper and have twice the memory of AMD servers. I’ve been standardizing on ARM.

I am hesitant of installing anything else though. I prefer to use mailinabox as-is. If the backup doesn’t work, so be it. I use external backup.

Based on the Moving to a New Box procedure, it should be enough to backup /home/user-data. Right?

I suppose I need to try it. Create a new box, restore /home/user-data, point my browser to the new box, and check if my settings and data are there.

I do not keep my mail in mailinabox. I move it periodically to separate dovecot server.

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That should work. Relatedly I use AWS graviton arm server which looks much cheaper than heater after briefly glancing at their site

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I tried it. It worked. Backing up /home/ is enough. There is no need to backup things like /etc/nsd/zones. They are generated by running mailinabox.

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A Hetzner ARM instance with 4 GB RAM, 40 GB SSD, 2 shared cpus, and practically unlimited bandwidth (20TB) costs € 3.79 / month (without VAT). A t4g.small AWS instance (2 GiB RAM) costs 0.0168/h = $12/month on-demand. This does not include the disk or bandwidth, which are charged separately. With a 1 year term paid up-front, you get 33% savings. A 4 GB AWS instance (t4g.medium) is twice the price. I abandoned AWS years ago. Hetzner’s pricing is also much simpler. There is a single monthly price and a single hourly price, and you automatically get whatever costs less for the amount of time that you use it.

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FYI it seems MIAB reinstalls the apt version on MIAB update so I had to uninstall it to get backups working when upgrading to v67.

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They only have AMD available in the US, a deal breaker for me.