Trouble connecting to other machines

Since the 0.21 release my box has been unable to communicate with other computers for backups. For Amazon backup I get:

Upload 's3://s3.amazonaws.com/mybucket/backup/duplicity-full.20161202T145010Z.vol1.difftar.gpg' failed (attempt #1, reason: error: [Errno 104] Connection reset by peer)

I was also using Borg to backup to a personal computer but it now returns the similar sounding:

Remote: Write failed: Broken pipe
Connection closed by remote host

I confirmed my AWS credentials and Borg setup are working from a different computer. I don’t see anything related in the logs and am unsure where to start trying to debug the issue.

I’m seeing similar issues but haven’t been able to pin it down. My box was already on master, but the issues started this week. So seems release unrelated for me at least.

When trying to backup to the borg server I found these logs:

sshd[2377]: Corrupted MAC on input.
sshd[2377]: ssh_dispatch_run_fatal: Connection from ■■.■■.■■.■■■ port ■■■■■: message authentication code incorrect

The connection itself seems to work but once the transfer starts I get the error mentioned above. Connecting directly via scp works with small files but when they begin to approach 10M I start to get Broken pipe errors.

I tried setting up a new Ubuntu 14.04 server and both borg and scp are able to upload to the destination as expected.

I found that when I upgraded my ssh on the non-MIAB box, things started to work again.

I checked the borg server and it is fully up-to-date with Ubuntu 16.10 (SSH 7.3p1, OpenSSL 1.0.2g) but the problem also extends to using duplicity with S3 where I don’t think SSH is involved. The MIAB server also can’t transfer between another Ubutnu 14.04 server, a second 16.10 server or my OpenSUSE Tumbleweed desktop; whereas all those computers can transfer between themselves.

Between S3, scp and borg the only common component seems to be OpenSSL but I’m at a loss where to start debugging that.