+++ This bug was initially created as a clone of Bug #629032 +++

[This was found while debugging why SELinux "sandbox -X" doesn't work on my machine]

kernel-2.6.35.4-12.fc14.i686
xorg-x11-server-Xephyr-1.9.0-4.fc14.i686

1. disable IPv6 module loading

  Either add a file to /etc/modprobe.d with

    install ipv6 /bin/true

or

    blacklist ipv6
  + disable all services that might set up ipv6, e.g. ip6tables

2. after boot make sure that "ipv6" isn't loaded:

    # lsmod | fgrep ipv6
    #

3. SELinux can be in Enforced or Permissive mode

    This only affects what kind of AVCs you'll receive. It hasn't anything to do with the problem.

4. start Xephyr

   (this is the command line used by sandbox -X)

    $ /usr/bin/Xephyr -title "test" -terminate -screen 1024x768 -displayfd 5
_XSERVTransSocketOpenCOTSServer: Unable to open socket for inet6
_XSERVTransOpen: transport open failed for inet6/l3f1199:0
_XSERVTransMakeAllCOTSServerListeners: failed to open listener for inet6
_XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
_XSERVTransMakeAllCOTSServerListeners: server already running
_XSERVTransSocketOpenCOTSServer: Unable to open socket for inet6
_XSERVTransOpen: transport open failed for inet6/l3f1199:1
_XSERVTransMakeAllCOTSServerListeners: failed to open listener for inet6
_XSERVTransSocketOpenCOTSServer: Unable to open socket for inet6
_XSERVTransOpen: transport open failed for inet6/l3f1199:2
...
... and so on and so on ...
...
_XSERVTransMakeAllCOTSServerListeners: failed to open listener for inet
_XSERVTransSocketOpenCOTSServer: Unable to open socket for local
_XSERVTransOpen: transport open failed for local/l3f1199:64510
_XSERVTransMakeAllCOTSServerListeners: failed to open listener for local
_XSERVTransSocketOpenCOTSServer: Unable to open socket for unix
_XSERVTransOpen: transport open failed for unix/l3f1199:64510
_XSERVTransMakeAllCOTSServerListeners: failed to open listener for unix

Fatal server error:
Failed to find a socket to listen on

--- Additional comment from Fedora End Of Life on 2012-08-16 17:23:25 EDT ---

This message is a notice that Fedora 14 is now at end of life. Fedora 
has stopped maintaining and issuing updates for Fedora 14. It is 
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