issue with openssh-server running in a libvirt based centos virtual machine

Darren Tucker dtucker at dtucker.net
Fri Jan 26 14:02:49 AEDT 2018


On 26 January 2018 at 06:44, Adrian Pascalau <adrian27oradea at gmail.com>
wrote:

> [...]
> debug1: SSH2_MSG_KEXINIT sent [preauth]
>
> Here the debug mode stops, and there is no login prompt shown on the
> Putty window.


This behaviour is often caused by a path MTU/fragmentation problem.

If you run "netstat" on both client and server and find the SSH TCP
connection you should see a "Send-Q" column.  This column is the number of
bytes in the TCP socket buffer that the other end has not acknowledged.  If
it is non-zero number that remains above zero or increases then IP
fragmentation is likely your problem and you need to fix whatever in your
environment is causing that.

-- 
Darren Tucker (dtucker at dtucker.net)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.


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