[RndTbl] sshd: Corrupted MAC on input.

Gilbert E. Detillieux gedetil at cs.umanitoba.ca
Tue Aug 4 13:28:30 CDT 2020

On 2020-08-04 12:55 p.m., Adam Thompson wrote:
> It's bizarre that you're getting this so consistently - the FCS plus the 
> checksum between them should trigger TCP retries long before the errors 
> percolate up to the application layer.

Which is why I was leaning toward either a NIC problem, or bad RAM. 
(There's no ECC on this box.)

> I can't remember, did you try disabling HW offload on both sending and 
> receiving ends already?  (Either end could trigger the SSH abort.)

I hadn't yet.  (I was trying a few other things first, such as changing 
MAC algorithms, and rebooting with the older kernel, neither of which 
seemed to affect things.)

I've now disabled both rx and tx checksum offloading.  We'll see if that 
makes a difference.


> On 2020-08-04 11:14, Gilbert E. Detillieux wrote:
>> Just FYI, I had an rsync fail just a while ago about 17 seconds (and
>> 253MB) into a file transfer.  Same error on the remote side.
>> After restarting, it died again, this time after 3m07s (and 2.6GB).
>> So, it is fairly random, yet consistent!  :P
>> Gilbert
>> On 2020-08-04 9:56 a.m., Gilbert E. Detillieux wrote:
>>> On 2020-07-31 11:42 p.m., Trevor Cordes wrote:
>>>> Gilbert, to confirm, your bug hits after you have transferred lots of
>>>> data, right?  It's not giving this error right at the beginning upon
>>>> connection, right?  Do you have any stats on approx how much data goes
>>>> across each time before the error hits?  Is it consistent or all over
>>>> the map?
>>> Yes, these are on large file transfers.  Yes, they are occasional, 
>>> and random.  But I had to restart a large (41-ish GB?) file transfer 
>>> 3 times last week due to repeated errors.  A typical nightly backup 
>>> results in 160 GB or so to transfer, and lately, the rsync fails 
>>> (somewhere along the way) more often than not.
>>> Gilbert

Gilbert E. Detillieux        E-mail:  <gedetil at cs.umanitoba.ca>
Dept. of Computer Science    Web:     http://www.cs.umanitoba.ca/~gedetil/
University of Manitoba       Phone:   (204)474-8161
Winnipeg MB CANADA  R3T 2N2  Fax:     (204)474-7609

More information about the Roundtable mailing list