VS: Strange problem with forwarding X11 traffic - solution !!!

Hi

Earlier I asked about a problem, se following copy of my mail. After geting som reponse from this group I finally isolated my problem. On the remote machine, in file sshd_config, I changed the parameter X11UseLocalhost from the default "yes" to "no". Then X11 forwarding worked flawlessly.

with best regards

Bent Vangli

-----Opprinnelig melding-----
Fra: Vangli, Bent [mailto:Bent.Vangli@Riksarkivaren.dep.no] Sendt: 11. februar 2003 11:41
Til: 'secureshell@securityfocus.com'
Emne: Strange problem with forwarding X11 trafic

Hi

Has someone any idea about this problem.

I have set up a remote RH 8.0 LINUX server with build in openssh support. I am fully capable of getting a ssh connection, also with client RSA sertificates to this machine from any of my LINUX machines. When I try to run a simple X-application, xload over this ssh connection, the process start but nothing are shown. The process is running but nothing shows up on local machine. This has worked flawless and works flawlessly on every other machine have set up. Its even works the other way around, using XDMCP I am capable of logging on to the remote server, getting a graphical interface and from there use ssh to connect to one of my local servers. This way ssh X11 forwarding works very well.

Do you need help?

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The following differences from my standard setup are reconized:

1. The first setup used an IP adress in my local segment (The X11 forwarding worked then). This was later changed before I placed the server remotely. I kept the servername and changed the DNS lookoop to reflect the new IP adress.
2. The server are effectively using three different aliases name all pointing to same IP adress. (Used by the apache server to run three virtual intranett websites) (I have three DNS lookups for this remote machine on my DNS server)

I have checked ssh_config and sshd_config files. I can't find any abnormalities.

What is going on? Which configuration file may I have overlooked? Do I need to set some special parameters?

With very best regards

Bent Vangli
IT-Manager
National Archives of Norway Received on Fri Feb 14 13:45:45 2003