Remote X App. on RH 7.3

[Miguel Covas]

I have a brand new RH 7.3 installed and I am unable to launch applications on our rp7400 servers (HP-UX 11.0).

I did
# xhosts +

then logged in , then
$ export DISPLAY=:0
then
$ gpm (Glance Plus Manager)

I get
Connecting to Display...
Error: Can't open display :0
Error: Couldn't find per display information

Am I missing something?
Some package that I did not install?

I have another workstation with RH 7.2 and it works fine. So it can be done...

[Stuart Browne]

When you say you did "xhosts +", I take it to mean you ran:

xhost +

(note: singular, as 'xhosts' doesn't exist). After issuing that command, what does 'xhost' on it's own report?

From the HP-UX machine, can you simply 'ping my.wkstation'? Just to ensure end-to-end connectivity.

Once you've done that, try using 'DISPLAY=:0.0', instead of just the ':0'. Some applications are picky.

Given the error messages you've given us, it would most likely be one of those things.

It doesn't look like you've missed installing any packages or anything of the like. Just looks like it's a niggly little annoying thing.

Something else to test would be to just try launching an xterm. I'm not 100% sure if the xterm command can take a '--display', but if it can, then issue:

xterm --display :0.0 &

and see if that connects..

[I_M]

Hi

Have you checked out the output of ipchains or iptables?

# ipchains -L
or
# iptables -L

This is a packet filter.
So if you have working RH7.2, compare the output would be the good idea to find the differences.

good luck

[Miguel Covas]

Hi Stuart,

xhosts was a typo.The workstation can be pinged (And since I telneted from it one can suppose that there is bidirectional communication).

appending either :0.0 or :0 to the ip address gives the same result.

Now, I have a new different Linux workstation which can connect with both DISPLAY definitions, so my guess is that there is something different.

[dirk dierickx · Accepted solution]

my guess is you have activated the firewall during install.

try this once before you want to start your application:

/etc/init.d/ipchains stop
/etc/init.d/iptables stop

if it works after that, you need to change your firewall settings.

change the type of FW with the 'lokkit' program.

or you can manualy edit the file: /etc/sysconfig/firewall

[Miguel Covas]

Hi Dirk, you did it!!

After stopping those services it
started to work.

[Stuart Browne]

Miquel, just wondering, is this machine exposed to the internet? Just thinking of the security of your PC.. You did, after all, just disable the firewall..

[Miguel Covas]

Hi Stuart,

the machine is behind a firewall. I suppose that I could do some fiddling with the local firewall just to find out the proper configuration, but it is just a workstation. We are replacing Linux for Windows and we are somewhat newbies having a Unix machine as workstation (although our servers are Unix machines)

[Stuart Browne]

*nod* just thought I'd check.

To make sure it doesn't come up again (as you don't really need it), you can do two things.

one: remove the contents of /etc/sysconfig/iptables

two: chkconfig --level 2345 iptables off

Either of these will stop it from blocking again when you restart.