Re: sshd

[Andrey Repin <anrdaemon@yandex.ru>]

Greetings, Ernie Rael!

> On 2/12/22 9:29 PM, Mark Geisert wrote:
>> Ernie Rael wrote:
>>> Hi all,
>>>
>>> I set up cygwin several years ago and have only had one system at 
>>> home. I've recently got a 2nd, linux.
>>>
>>> I've used ssh locally under cygwin, primarily to get a term for a use 
>>> with admin priv. And I can ssh from cygwin to the linux machine. On 
>>> cygwin I see
>>>
>>>     $ ps -ef |grep sshd
>>>     cyg_serv     255     254 ?          Feb  1 /usr/sbin/sshd
>>>
>>> But ssh from linux to cygwin hangs (finally times out). Ping works 
>>> linux --> windows.
>>>
>>> I must have run ssh-host-config way back when. Can I just run it again?
>>>
>>> Suggestions for something else to try and/or triage the problem?
>>
>> You might try the following.  Determine the Windows pid of your sshd 
>> process, then use netstat to see if that process is listening on the 
>> sshd port.  Here's what a successful check looks like:
>>
>> ~ ps -as|grep sshd
>>   42834 ?          Jan 16 /usr/sbin/sshd
>>
>> ~ ps -lp 42834
>>       PID    PPID    PGID     WINPID   TTY         UID    STIME COMMAND
>>     42834   42832   42834       5972  ?         197612   Jan 16 
>> /usr/sbin/sshd
>>
>> ~ netstat -ao|grep 5972
>>   TCP    0.0.0.0:22             zotac:0 LISTENING       5972
>>   TCP    [::]:22                zotac:0 LISTENING       5972
>>
>> If the two output lines aren't there, I'd suspect a Windows firewall 
>> has TCP port 22 walled off.  ("zotac" is my machine name; you'll see 
>> something different there.)
>> HTH,
>>
>> ..mark
>>
> Thanks Mark,

> Doesn't seem to be a firewall issue. NetStat took about 90 seconds.

> $ ps -lp 255
>        PID    PPID    PGID     WINPID   TTY         UID    STIME COMMAND
>        255     254     255       4176  ?           1006   Feb  1 
> /usr/sbin/sshd

> $ netstat -ao | grep 4176
>    TCP    0.0.0.0:22             spirit:0 LISTENING       4176
>    TCP    [::]:22                spirit:0 LISTENING       4176

Open Windows Firewall (cygstart WF.msc), find all your sshd rules and trash
them. Manually create (or tweak Windows sshd one) a single rule for port
rather than executable.
Additionally, to resolve conflicts with stock sshd, create a file
%ProgramData%\ssh\sshd_config with single line `Port 2022` (for example).


-- 
With best regards,
Andrey Repin
Monday, February 14, 2022 9:34:52

Sorry for my terrible english...