One ssh hangs on exit, the other doesn't

[Steffen Nurpmeso]

Matthew Dillon wrote in <CAOZ7CpDFe8H4UW1hwg69w8V=dX8a-=RFEDrZtA7u05p2-d\
VHgQ at mail.gmail.com>:
 |On Thu, Dec 5, 2019 at 12:15 PM Steffen Nurpmeso <[1]steffen at sdaoden.eu[\
 |/1]> wrote:
 ||Pierre Abbat wrote in <12216388.yjY6BSWRI4 at mooncat>:
 || |On Thursday, 5 December 2019 03.48.18 EST Harald Brinkhof wrote:
 || |> Maybe some background processes keep running and prevent the X \
 ||program \
 || |> from
 || |> sitting down?
 ...
 || |The examples at the top of that page don't make sense. If I start an \
 || |xterm in 
 || |an ssh session, and log out of the ssh session with the xterm still \
 || |running, I 
 || |expect ssh to keep running until I close the xterm. When I ssh into \
 || |leopard, 
 || |my local mail server, and forward the mail ports, the ssh session \
 ||hangs on 
 || |exit, because kmail still has the mail ports open.
 || |
 || |When I shelled into zyxomma, I exited each program before logging out \
 || |of ssh. 
 || |I don't understand why one ssh session closed and the other hung.
 |
 ||Does it still hang when ControlMaster exits?
 ||I have seen this on Linux->Linux (same host even) with
 ||X forwarding in muxer sessions, but it went away as rolling
 ||updates flew by.  (At the moment i have 
 |
 ||  Load key "/home/steffen/....local_ed25519.pub": invalid format
 |
 ||that that makes no sense :})
 ...

 |ssh won't exit unless all virtual links, such as the X forwarding, \
 |are also gone.  I think there are some bugs related to that (I'm pretty \
 |sure it isn't dragonfly specific).  So running with X forwarding 
 |can cause the situation you describe.

Yes indeed it did!

  #?0|kent:tmp$ ssh -vvv web at localhost
  OpenSSH_8.1p1, OpenSSL 1.1.1d  10 Sep 2019
  debug1: Reading configuration data /home/steffen/.ssh/config
  debug1: /home/steffen/.ssh/config line 8: Applying options for localhost
  debug1: /home/steffen/.ssh/config line 66: Applying options for *
  debug1: Reading configuration data /etc/ssh/ssh_config
  ...
  debug3: record_hostkey: found key type ED25519 in file ...
  ...
  debug1: Next authentication method: publickey
  debug1: Offering public key: ..local_ed25519.pub ED25519 ... explicit
  debug3: send packet: type 50
  debug2: we sent a publickey packet, wait for reply
  debug3: receive packet: type 60
  debug1: Server accepts key: ...local_ed25519.pub ED25519 ... explicit
  debug3: sign_and_send_pubkey: ED25519 ...
  debug3: sign_and_send_pubkey: signing using ssh-ed25519
  Load key "...local_ed25519.pub": invalid format

Hmm.  But here indeed all that happened is that i must have missed
adding the key via ssh-add.  Since that happens via a script that
adds a bunch of SSH keys and a GPG key in a row, repeatedly
prompting for passwords, with me satisfying the prompt via copy
and paste, it seems i made a copy+paste error for this key
beforehand.  Uups.  Now fixed.

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)