[jboss-as7-dev] [jboss-as] Added support for -b command-line binding functionality (#248)

[Brian Stansberry]

Continuing the discussion from 
https://github.com/jbossas/jboss-as/pull/248 on the regular dev list, so 
it has higher visibility.

On 9/4/11 4:40 PM, dobozysaurus wrote:
> Yep, Bob's right - shorthand is great for usability. Right now in AS7, if you want to, say, bind the public interface to any address, instead of just using the -b arg as we've been using for a while now, users have to:
>
> 1. Open standalone.xml
> 2. Find the public logical interface XML configuration section.
> 3. Delete the<inet-address value="127.0.0.1" />  element
> 4. Add<any-address />  in its place.
>
> That's four steps where one existed before, and on step #4, it's not immediately obvious to them that they should now use<any-address />  instead of 0.0.0.0 for a wildcard binding.
>
> The new configuration model is super awesome, but little things like this definitely help people make the transition from previous AS versions to AS7.
>

First, thanks for the patch; I didn't say that before. :)  Better 
handling of "0.0.0.0" in the inet-address element is definitely needed. 
So let's just assume any need for step #4 will go away.

To achieve the goal of controlling the external sockets of a standalone 
server with a simple -b, the standard standalone*.xml configs we ship 
would need to be modified like this:

<interfaces>
   <interface name="management">
     <inet-address value="${jboss.bind.address.management:127.0.0.1}"/>
   </interface>
   <interface name="public">
     <inet-address value="${jboss.bind.address.public:127.0.0.1}"/>
   </interface>
</interfaces>

A necessary precondition to that is the management console included in 
master not barf if it queries the server and gets back a ModelNode of 
ModelType.EXPRESSION instead of ModelType.STRING. Heiko/Stan, where does 
that stand?

Once the console can support it, I think it's a good idea to have the 
standard configs use an expression.

Once that's there, I'm kinda ok with the use of -b as a cmd line arg to 
a standalone server. I see the ease of use benefits, and -b is a 
long-standing JBoss AS tradition. The thing that makes me queasy is it's 
a long-standing tradition, but now with new and different wrinkles:

1) It's now much easier to make the -b setting meaningless. If someone 
changes the name of the "public" interface to something else or gives it 
a criteria other than <inet-address 
value="${jboss.bind.address.public:127.0.0.1}"/> the -b setting will be 
completely ignored. You could break -b in earlier AS releases as well, 
but you had to try much harder to make it completely meaningless.

This is the kind of thing that can be explained in a good FAQ, which is 
why I'm kinda ok with the whole idea.

2) It doesn't do anything if you run domain.sh, or if it will the 
semantics are presently undefined. A command line arg passed to 
domain.sh potentially impacts multiple processes: ProcessController, 
HostController, 0..n app server instances.


-- 
Brian Stansberry
Principal Software Engineer
JBoss by Red Hat