As usual, late to the thread.

I'll use C) then:

> > C) on another workstation :
> > 
> >     - close the browser and re-open it.
> >     - in the browser, find the place where you can "clear the cache".
> >     - do it (clear the cache)
> >     - request the URL :
> >               
>   http://adm138/InfoViewApp
> > 
> >     - indicate the result here :
> > 
> > 
> > A:  Internet Explorer cannot display the webpage

This usually means that the other workstation cannot translate between the name 
you gave the host on the other workstation (adm138) and the IP address of your 
server.

I also noticed that while you use the fully qualified name in the other example 
(www.fmdreports.vcu.edu) you use the short name in your tests (adm138).

There are several things to try here, to see where the breakdown is.  I'll use 
numbers since everyone else is using letters.

1. From another workstation, open a DOS window (if it's Windows) or a UNIX 
shell command (if it's UNIX), and type the following:

ping adm138

1a) If you get:
Ping could not find the host adm138, then the other workstation does not know 
how to translate between the name and the IP address.

1b) If you get:
Four lines with a bunch of numbers, then the other workstation knows how to 
translate between the name and the IP address

2. From another workstation, open a DOS window (if it's Windows) or a UNIX 
shell command (if it's UNIX) and type the following:

ping adm138.fmdreports.vcu.edu

2a) If you get:
Ping could not find the host adm138.fmdreports.vcu.edu, then the other 
workstation does not know how to translate between the name and the IP address.

2b) If you get:
Four lines with a bunch of numbers, then the other workstation knows how to 
translate between the name and the IP address

adm138.fmdreports.vcu.edu may be the fully qualified name, but this depends on 
how your network administrator has set up something called DNS.

Firewall check
==============

Windows comes with a built-in firewall.  On XP/Professional it's located in 
Start->Control Panel->Network Connections.  You'll have to single-click on the 
active network (the one your server connects to) to see Change Firewall 
Settings on the left hand side.

Once you click on that (Change Firewall Settings), you should be able to edit 
the settings by selecting Exceptions tab.  Hopefully you'll see two entries for 
Java(TM) Platform SE Binary.  Make sure that the JRE you're using to run Tomcat 
is there (by clicking on edit and reading the properties).

Short term fix (once you've checked your firewall)
==================================================

If you have administrative privileges on the other workstation (Windows) or 
root access (UNIX), you can add some information in a file called hosts.  On 
Windows, it's located in the %windir%\System 32\drivers\etc directory.  In UNIX 
it's located in /etc

The line you need to add is the following:

aaa.bbb.ccc.ddd adm138

where aaa.bbb.ccc.ddd is the IP address of the machine with your Tomcat server.

If the fully qualified name is supposed to be adm138.fmdreports.vcu.edu, then 
add this line instead to the hosts file

aaa.bbb.ccc.ddd adm138 adm138.fmdreports.vcu.edu

where aaa.bbb.ccc.ddd is the IP address of the machine with your Tomcat server.

Long term (proper) fixes
=========================

There are really two parts to this fix.  The first part is to get your network 
administrator to add this hostname and IP address to your campus DNS server.  
The DNS server is responsible for translating between human-readable names and 
IP addresses.  Once the name you have chosen for your server is in DNS, all 
machines using DNS servers will know how to interpret the name of the host.

The second part of the fix is to alter your virtual host definition in 
server.xml.  In general, it's a good idea to only use fully qualified names in 
the server.xml file.

So, in part, your host element should look like this:

<Host name="fully-qualified-host-name" . . . . >

</Host>

For example:

<Host name="adm138.fmdreports.vcu.edu" . . . >

</Host>

However, if you want to have this virtual host respond to other names, you can 
add aliases for each name.  To do that, just add an alias element for each name 
you want.

<Host name="fully-qualified-host-name" . . . .>
  <Alias>some-other-name</Alias>
  <Alias>still-another-name</Alias>

</Host>

For example:

<Host name="production.fmdreports.vcu.edu" . . . >
  <Alias>adm138.fmdreports.vcu.edu</Alias>
  <Alias>another.fmdreports.vcu.edu</Alias>

</Host>

If you want those aliases to be visible to other select workstations, then you 
will have to edit the hosts file for each workstation like I've shown above.  
Obviously, this is not a permanent fix if you have to edit 1000s of hosts on 
campus.

If you want to have those alias names reachable from workstations that are not 
your server, then tell your network administrator what those names should be.  
Please remember if these names are going to be globally visible, you will have 
to use fully qualified names, not something like adm138.

Host Name Resolution Background
===============================

Finally, there's a bit of magic happening on your workstation depending on how 
it's configured.  As I've said above, all host names should be fully qualified. 
 If that's the case, then how does mapping adm138 to an IP address work?

The code that maps a name to an IP address queries its own host name, the hosts 
file, and configured network servers.  This is configurable with UNIX, but not 
(if I remember correctly) under Windows.

When asking a server, the code that requests the information can add a domain 
name suffix (in your case it might be fmdreports.vcu.edu or vcu.edu).  That 
means for the first request to any network server, your workstation will tack 
on that information to the end of the name you give it.

In other words adm138 becomes adm138.fmdreports.vcu.edu before it gets sent to 
the server as a question.  There are rules about truncating the suffix 
(fmdreports.vcu.edu, then vcu.edu).

So depending on your workstation's configuration, the search code would do this 
on getting adm138:

1. Is it my hostname?
   Yes - great, we're done

2. Is it in my hosts file
   Yes - great, we're done

3. Add my Primary (or default) domain (may be fmdreports.vcu.edu)

4. Ask the server for adm138.fmdreports.vcu.edu
   Yes - great, we're done

5. Ask the server for adm138.vcu.edu
   Yes - great, we're done

If all responses were "not found" (NXDOMAIN), then you get a page not found 
error in IE.

Summary
=======

1. Put fully qualified host names the <Host></Host> element in server.xml.
2. Put in any aliases (qualified or not) in the <Alias></Alias> element 
   of server.xml
3. Get your network administrator to add all fully qualified names to DNS
4. Put all unqualified names in hosts files of hosts that you want to 
   connect to your server
5. Remember that the use of hosts files is purely for testing.  DNS 
   should be used for all production work

Hopefully that will get you up and running.  If not, then your network 
administrator has blocked access to port 80 from other parts of the network.  
This is reasonable for example, to prevent students from running their own web 
servers.  You'll have to ask your network administrator to grant access to port 
80 (as a server) for your particular IP address.

I apologize for the length.  Hopefully that will complete your connectivity and 
get you up and running.

Mark




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