Re: NetBSD-7 SSH disconnects

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

On Mon, 18 Jan 2016 01:53:05 -0500,  marcotte%panix.com@localhost (Brian Marcotte)
wrote:

> Since upgrading to NetBSD-7.0, several of our users started reporting
> occasional SSH disconnects from our servers with a message like one of
> these:
> 
> 	Corrupted MAC on input. Disconnecting: Packet Corrupt
> 
> 	ssh_dispatch_run_fatal: Connection to <ip>: message authentication 
> 	code incorrect
> 
> These are reported from people using a variety of clients like OpenSSH
> on FreeBSD and MAC or PuTTY on Windows.
> 
> Has anyone else experienced this since upgrading to NetBSD-7?

I saw them frequently when connected to a machine running -current
(7.99.*), but usually only under heavy traffic (e.g., building a release).
Searching t3h intarw3bz suggested NIC problems (broadcom hardware offload
functions) to faulty memory.

The odd thing was that it only happened when I connected to that machine
"directly" (nothing but routers/switches between my host (netbsd-7/i386)
and it (netbsd-HEAD i386)).  If I SSH'd to any other machine first--whether
to another machine on the same switch as the problem machine or to
machine on a different subset of routers--and then SSH'd to the problem
machine, the problem disappeared.

The intermediate machines on the same switch as the problem machine were
running NetBSD-7 (either i386 or amd64).  The one on a different subset
of routers was running FreeBSD/amd64 10.1-STABLE.

Since then I have had the machine on my own LAN and it did not exhibit
the problem.

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