HP-UX 11.23 System No longer working with Exceed

[Greg Santa]

I have an 11.23 server that I can no longer connect to with Exceed, but I am not sure what might have changed. I have checked the Xaccess file, the hosts, hosts.allow, and hosts.deny files, and everything looks fine. We use the XDMCP Broadcast mode, and when I fire up Exceed I see the server listed in the Display Chooser window. However, when I pick the server and click OK, the CDE login screen never appears. The last line I see in my PC's Exceed log is "XDMCP status: XDM_AWAIT_MANAGE_RESPONSE", and in my 11.23 server's Xerrors file I see "error (pid *****): Server open attempt #0 failed for [PC_NAME]:0, giving up". It looks like the call is going out from the PC to the HP-UX server, but the server can't return the response. What else can I check to figure out why this is no longer working?

[Torsten.]

Based on my experience I would start asking for new firewalls on network or your PC.

...

If I were started from this point last time this would have saved me some hours.


:-)

[Rita C Workman]

Did you check the Xconfig in Exceed.
Check Exceed/Network and Communication
Does it show - XDMCP Broadcast and "0" for display number
Click on Configure
Does it show
Display Class = HCLpcXserver
Key: Mine happens to be blank
Local Port: 296
Remote Port: 288
I have 'Exit Kill All Clients' checked
Under XDMCP Broadcase
Host List File checked.
Click on Edit...make sure the entries are right.
Use Broadcast Address checked. Confirm the address here too (255.255.255.x - depends on your shop for exact settings)

Not sure if this will help, but it's a start for you.
Rgrds,
Rita

[Greg Santa]

All users on all PC's are no longer able to connect. I believe this is a problem on the HP-UX server side, not the PC side. What else can I check on my 11.23 server that may cause this issue?

[Torsten.]

Can you try with another server?

I don't want to sound like a broken record, but think about the firewall...

[Greg Santa]

These 2 systems are in the same subnet with no firewall in between them. This is the only server on this network that has access through Exceed. I may have to configure another server for Exceed access to see if I can get it to work.

[Torsten.]

I tell all this, because some months ago we get a new enterprise solution for antivirus for all PCs with integrated firewall, centrally managed and pushed. The first default configuration was to close and block almost everything on PCs, no user was able to change this. Everything what was working yesterday, today it doesn't. Even if you disabled some minor parts of this protections, it was enabled some minutes after. Now think about how many "unusual" ports your applications is using.

It's just a thought ...

[Rita C Workman]

...hmmm... I run Exceed from my PC's and just checked connecting to the 11.23 PARisc boxes and even to one 11.31IA Virtual Machine and had no connection issues. The login screen came right up.

So I definitely am leaning towards what Torsten is bringing up. I know when the Windows/Network guys do some security patch pushes or start locking down ports I've had strange issues and doors locked causing me to run down and "kindly and diplomatically express my concerns".

Never hurts to ask them....

/Rita

[Bill Hassell]

Xwindows is a very complex protocol and trying to troubleshoot a remote desktop login is very difficult. Instead, verify that you have any Xwindow connectivity at all by logging in with your PC (telnet or ssh). Start Exceed as an Xwindow display server only (don't try to use the special login screen). Then export your PC's IP address (don't use a PC name) like this:

export DISPLAY=12.34.56.78:0.0

Then run xclock on the HP-UX server:

/usr/bin/X11/xclock

You should see the Xwindow clock popup on your PC screen. (check to see if it starts iconified). If you don't get anything and xclock gives up with something like:

Error: Can't open display:
Error: Couldn't find per display information

then your network team has "improved" the security by blocking Xwindow traffic. This test bypasses all the complicated XDM and desktop display code and just sends plain old X11 messages to your PC's Xwindow emulator.