Re: e1000, sshd, and the infamous "Corrupted MAC on input"

[Matt Mackall <mpm@selenic.com>]

On Wed, Feb 02, 2005 at 10:44:14PM -0500, Ethan Weinstein wrote:
> Hey all,
> 
> I've been having quite a time with the e1000 driver running at gigabit 
> speeds.  Running it at 100Fdx has never been a problem, which I've done 
> done for a long time. Last week I picked up a gigabit switch, and that's 
> when the trouble began.  I find that transferring large amounts of data 
> using scp invariably ends up with sshd spitting out "Disconnecting: 
> Corrupted MAC on input."  After deciding I must have purchased a bum 
> switch, I grabbed another model.. only to get the same error.
> Finally, I used a crossover cable between the two boxes, which resulted 
> in the same error from sshd again.

Well ssh isn't an especially good test as it's hard to debug.

Try transferring large compressed files via netcat and comparing the
results. eg:

host1# nc -l -p 2000 > foo.bz2

host2# nc host1 2000 < foo.bz2

If the md5sums differ, follow up with a cmp -bl to see what changed.

Then we can look at the failure patterns and determine if there's some
data or alignment dependence.

-- 
Mathematics is the supreme nostalgia of our time.