Unable to login to IB - again com.sap.engine.services.rmi_p4.P4IOException

Question

We have installed a new PI 7.1 system and at he moment I have the problem that I can't login into the IB tools. I found a lot of threads with this problem but I can't find a solution for my specific problem. Have a look at the well known error log:
com.sap.aii.utilxi.misc.api.ReconnectRuntimeException: Cannot connect to server using message server: ms://MYHOST:8100/P4
     at com.sap.aii.ib.clsif.login.EJBHomeFactory.getInitialContext(EJBHomeFactory.java:668)
     at com.sap.aii.ib.clsif.login.EJBHomeFactory.connect(EJBHomeFactory.java:461)
     at com.sap.aii.ib.clsif.login.EJBHomeFactory.initRemoteFactory(EJBHomeFactory.java:133)
     at com.sap.aii.ib.clsif.login.LoginServiceImpl.login(LoginServiceImpl.java:176)
     at com.sap.aii.ib.clsif.login.LoginServiceImpl.login(LoginServiceImpl.java:121)
     at com.sap.aii.ib.clsif.login.LoginServiceImpl.login(LoginServiceImpl.java:109)
     at com.sap.aii.ib.gui.login.SplashLoginFrame$LoginController.doTrial(SplashLoginFrame.java:960)
     at com.sap.aii.ib.gui.login.SplashLoginFrame$LoginAction$1.run(SplashLoginFrame.java:832)
     at java.awt.event.InvocationEvent.dispatch(Unknown Source)
     at java.awt.EventQueue.dispatchEvent(Unknown Source)
     at com.sap.aii.utilxi.swing.toolkit.Guitilities$EventProcessor.dispatchEvent(Guitilities.java:319)
     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
     at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: com.sap.engine.services.jndi.persistent.exceptions.NamingException: Exception while trying to get InitialContext.
     at com.sap.engine.services.jndi.InitialContextFactoryImpl.getInitialContext(InitialContextFactoryImpl.java:488)
     at javax.naming.spi.NamingManager.getInitialContext(Unknown Source)
     at javax.naming.InitialContext.getDefaultInitCtx(Unknown Source)
     at javax.naming.InitialContext.init(Unknown Source)
     at javax.naming.InitialContext.<init>(Unknown Source)
     at com.sap.aii.ib.clsif.login.EJBHomeFactory.getInitialContext(EJBHomeFactory.java:653)
     ... 15 more
Caused by: com.sap.engine.interfaces.cross.EXTstinationException: cannot establish connection with any of the available instances:
MYHOST.DOMAIN.EXT:50104 Reason: com.sap.engine.services.rmi_p4.P4IOException: Cannot open connection to host: 172.24.205.193 and port: 50104
     at com.sap.engine.interfaces.cross.EXTstination.getNextAvailableBroker(Destination.java:59)
     at com.sap.engine.interfaces.cross.EXTstination.getRemoteBroker(Destination.java:35)
     at com.sap.engine.services.jndi.InitialContextFactoryImpl.getInitialContext(InitialContextFactoryImpl.java:352)
     ... 20 more
As you can see I call the IB via a pure hostname "MYHOST". But in the last step you can see the the FQDN  "MYHOST.DOMAIN.EXT"was used. That brings me into trouble because these are different IP's. I can't reach the MYHOST.DOMAIN.EXT IP and that's why I can't login into the IB.
If I add an entry in my local host file for MYHOST.DOMAIN.EXT with the IP address I can reach all works fine but this solution is unacceptable.
The key question is why the IB uses this FQDN. I can't find any setting where this FQDN is used. I have checked the complete exchange profile, the sld and and and u2026. I always find only the pure hostname MYHOST.
Additionally I have to say that we have already a PI 7.1 system (DEV) whre I can use all tools. But this is a migrated system (from 3.0). I have only problems with that new installed empty system.

Answer 1

Thanks Barry. I've checked all connections. They all use the short name and all work.
Thanks Joel, but I think you get me wrong. That's why I will explain it a little bit better.
I can use the IB if I manipulate my own hosts file but this is in my eyes not the right way. As I have written I can use my PI dev system without that kind of manipulation.
My new PI system is at our computer centre. The PI machine has two network interface and I can use only one of these two. As you can see at the error log the full name points to 172.24.205.193 but I only can reach the 172.20.02.193 address. For this second IP we have an entry at our DNS server. The other one (FQDN) comes from the computer center DNS server. Of course I can overwrite it with an entry in my local hosts file but I think that isn't a good solution.
The key question is: Why the full qualified domain name "MYHOST.DOMAIN.EXT" is used instead of the short name.
I call the IB via the web page
http://MYHOST:50100/dir/start/index.jsp
And as you can se at the log the first call goes to this address. But then a second call goes to MYHOST.DOMAIN.EXT:50104. And I can find any setting (exchange profile and so on) where this full qualified domain name is specified.