spawned ssh processes are left in defunct state when their task completed

[AZ]

Binary package hint: dish

Using dish to run apt-get update on a bunch of machines works fine, as long as the hosts are proccessed sequentially.
Using -f or -F, the commands still get run, but after the ssh connection is closed, the ssh process stays in <defunct> state
and never returns - so does dish. I would have expected dish to exit after all clients have completed when using -f .
Ssh login is done using an authorized key and sudo does not require a password to be entered for the issued commands.
Also, no output (except for errors) should be produced by apt-get normally. The hosts are read from a file using -g.

10057 pts/1 S+ 0:00 | \_ /bin/sh ./bin/updater.sh
10134 pts/1 Sl+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 dist-u
10155 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10173 ? Zs 0:00 | | \_ [ssh] <defunct>
10156 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10171 ? Zs 0:00 | | \_ [ssh] <defunct>
10157 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10172 ? Zs 0:00 | | \_ [ssh] <defunct>
10158 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10192 ? Zs 0:00 | | \_ [ssh] <defunct>
10159 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10189 ? Zs 0:00 | | \_ [ssh] <defunct>
10160 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10164 ? Zs 0:00 | | \_ [ssh] <defunct>
10161 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10163 ? Zs 0:00 | | \_ [ssh] <defunct>
10165 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10193 ? Zs 0:00 | | \_ [ssh] <defunct>
10170 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10181 ? Zs 0:00 | | \_ [ssh] <defunct>
10174 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10180 ? Zs 0:00 | | \_ [ssh] <defunct>
10175 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10186 ? Zs 0:00 | | \_ [ssh] <defunct>
10182 pts/1 S+ 0:00 | \_ /usr/bin/expect -- /usr/bin/dish -p0 -f -T 1200 -p0 -e sudo DEBIAN_FRONTEND=noninteractive /usr/bin/apt-get -q2 di
10191 ? Zs 0:00 | \_ [ssh] <defunct>

[AZ (m-dev)]

This has been with ubuntu lucid

Package: dish
Priority: optional
Section: universe/admin
Installed-Size: 196
Maintainer: Ubuntu Developers <email address hidden>
Original-Maintainer: Dimitar Ivanov <email address hidden>
Architecture: all
Version: 1.17.1-1
Depends: expect
Recommends: openssh-client | ssh, telnet | inetutils-telnet | telnet-ssl
Filename: pool/universe/d/dish/dish_1.17.1-1_all.deb
Size: 47926
MD5sum: 63ea602fb395d1bc8f1cff4fbe409190
SHA1: 03bb2576adb42914b6e7e1e6387fe477077b918e
SHA256: 78a96ec12a170b4e025d0831d8ac9dd3741897978942b4f07a543cf4abf7b8c3
Description: the diligence/distributed shell for parallel sysadmin
 Dish executes commands simultaneously on several systems via 'ssh', 'rsh',
 'telnet', 'mysql', or other command-line programs. It also makes easy the
 distribution of files by 'scp' and 'rcp', or a remote password change.
 Dish could be used as a flexible tool for managing large number of any
 type of hosts such as (clustered) servers, switches, databases, etc.
Homepage: http://dish.mirendom.net
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Origin: Ubuntu

[Launchpad Janitor (janitor)]

This bug was fixed in the package dish - 1.19.1-1

---------------
dish (1.19.1-1) unstable; urgency=low

  * New upstream release
  * Standards-Version changed to 3.9.4
  * New entry in dish.links:
    '/usr/share/doc/dish/changelog.gz' points to '/usr/share/doc/dish/NEWS.gz'
  * Clean exit on timeout: all spawned processes terminated (Ubuntu LP: #661659)

 -- Dimitar Ivanov <email address hidden> Thu, 19 Sep 2013 18:12:56 +0200