Problems with sshd

[Noel]

On 7/15/2011 10:12 PM, Paul Schmehl wrote:
> I manage a small hobby website for some friends. The system
has been running fine for quite a while, but suddenly the
owners are having problems using WinSCP to transfer files to
the server. The only thing that has changed recently is their
internet service, and I'm inclined to think that's the cause.
They are using a Verizon hotspot, whatever that is. (They live
in the country, and options for internet service are limited.)
 
mobile hotspot - cellphone data connection rebroadcast on
local wifi (google mifi).   I've used Verizon's.  Quality of
the connection depends on the quality of the cellphone signal,
and can range from very good to "connected but unusable".
 
> But I'm the thorough sort, so I've enabled verbose logging
and been googling for possible causes. One thing I've noticed
is that their IP address changes quite frequently, but this
snippet from the log shows that it also happens with the same
IP. (I changed the username to protect their privacy.)
 
They will get a new IP every time the device
disconnects/reconnects.  If they aren't turning it off and
back on, this is an indicator of the connection dropping
completely.
 
> Checking the archived logs, which go back several months, the
"error: ssh_msg_send: write" entry appears occasionally
whenever they login using WinSCP, so I assume it's some
incompatibility about the program that rears its ugly head
from time to time. I suspect it has no significance wrt this
particular problem.
 
We use winscp (occasionally over cellular) and get no such
errors.  I'm guessing the message means it couldn't write to
the socket because the connection dropped.
 
> Any thoughts on possible things to check for would be most
welcome.
 
I think it's an inadequate data connection.  Sometimes
repositioning the mifi will help -- try the other side of the
house or near a window.
 
 
  -- Noel Jones