Hash Sum Mismatch network error?


New Member
Jul 8, 2023
I'm on a fresh install, the only changes have been disabling the enterprise repo and enabling the community repo. I get these hash sum mismatch errors on all nodes(all fresh) on my network. The reported filesize is correct, but all hashes fail. I've tried a few fixes from this post, but none have fixed the issue. I think, because errors persist across installs, the issue must lie with a network setting somewhere(I use Ubiquiti). Could it be possible I'm actually being MitM'ed? How would one even know?

Any suggestions are appreciated, and thanks in advance!
Last edited:
are you using a proxy? usually this boils down to one of those three:
- proxy/MITM interfering with the download
- broken memory corrupting the file (unlikely if the messages are always identical even with clearing the local cached files)
- mirror being broken (you could try "ftp.debian.org" instead of "ftp.us.debian.org", it should hit a CDN and be plenty fast anyway)
Looks like that fixed the errors from ftp.us.debian.org, but I'm still getting a bunch of the same errors from security.debian.org and download.proxmox.com. The fact that this is happening across repos makes me think either MitM, or some network setting specific to my environment.
or whatever was interfering doesn't any more ;)
Yep, eventually I tracked it down to a little 5 port tp-link switch that I thought was unmanaged, but in fact was taking my gateway address as it's factory default. Go figure.
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