Comment 7 for bug 561750

- there is no respawn option in /etc/init/squid.conf (but I think this wouldn't normally be a problem, except when squid crashed by itself)

- there is exactly one thing that does something to squid when the dsl-interface is brought up (I have resolvconf installed which is suggested by the squid package)

  /etc/resolvconf/update-libc.d/squid

which contains the command
  'invoke-rc.d squid reload'

This command does the wrong thing, it stops squid:

root@rechner6:~# start squid
squid start/running, process 3328

(now squid is usable)

root@rechner6:~# /etc/resolvconf/update-libc.d/squid
Rather than invoking init scripts through /etc/init.d, use the service(8)
[...]

root@rechner6:~# status squid
squid stop/waiting

(the squid/cache.log shows the normal shutdown sequence)