Failed to allocate internet-domain X11 display socket.

[Matt Hearn]

Hi all! We recently upgraded some of our 11.11 and 11.23 servers' SSH to 5.30.007. For one of them, when we try to connect via "Reflections," we get prompted for a password and then nothing happens. The error in the syslog is:

Apr 27 09:07:01 testbox sshd[1951]: error: Failed to allocate internet-domain X11 display socket

Google mentions a bug in Solaris, but nothing for HP. It seems to be working okay on our other HP servers, and oddly enough if I ssh from another server I get right in. Thanks!!!

[Matti_Kurkela]

"Reflections"? You mean "Reflection X", a Windows application that allows you to use X11 applications remotely, right?

When using SSH with X11 forwarding (like Reflection X would probably do), sshd attempts to allocate a TCP port in the 6010+ range. The first SSH user that requests SSH forwarding gets port TCP/6010 (DISPLAY=localhost:10.0), if that port is occupied, TCP/6011 is used instead, etc.

Apparently something prevents sshd from allocating such a port in your case. Are the ports 6010... occupied by something else?
(If you have lsof installed, run "lsof -i tcp:6010" to see if port 6010 is in use. If you don't have it, use "netstat -af inet" and look for port numbers 6010 and above in the "Local Address" column.

If you make a command-line SSH connection from another server (without using the -X option that requests X11 forwarding), the extra TCP port is not required and the connection will succeed.

MK