[jboss-as7-dev] Management Console: changing values that require a restart

[Brian Stansberry]

On 8/22/11 12:04 PM, Andrig Miller wrote:
>
>
> ------------------------------------------------------------------------
>
>     *From: *"David Bosschaert" <david at redhat.com>
>     *To: *"jboss-as7-dev at lists.jboss.org Development"
>     <jboss-as7-dev at lists.jboss.org>
>     *Sent: *Monday, August 22, 2011 3:52:11 AM
>     *Subject: *[jboss-as7-dev] Management Console: changing values that
>     require a restart
>
>     Hi all,
>
>     Just like to get the general feeling about this.
>
>     In the Management Console and via the Detyped API you can in some cases
>     modify configuration that requires a restart in order to become
>     effective. I'd like to find out what the general feeling is about this:
>
>     Option 1: make it editable via the Console and display a message that
>     changing this configuration requires a restart.
>
> Anything that should be able to be changed should be able to be changed
> through the UI, so Option 1 is the way to go.

Yes. The OperationContext that is passed into an OperationStepHandler 
allows the handler to tell the controller that a reload or restart[1] is 
required. (The base classes subclassed by many of the handler take care 
of this for you.) Any operation that puts the controller in a 
reload/restart required state will result in extra response headers 
being included with the response indicating this, and if the controller 
is already in that state a response header will also indicate that.

What's missing is standard metadata that should be part of the 
description of any writable attribute or of any operation that may 
trigger a restart-required. This metadata allows a console to tell the 
client in advance that they are about to trigger a restart-required 
situation. Now's the time to settle that metadata.

But I'm going to try and do that on this thread, as it affects the 
metadata and needs a response:

http://lists.jboss.org/pipermail/jboss-as7-dev/2011-August/003414.html

[1] A "reload" is a restart of the processes root service, a "restart" 
is a full process restart. A reload is much faster (say 200-300 ms) and 
almost always serves the purpose, but at this point isn't available for 
a domain managed server.

> Certainly, a message that
> says it won't take affect until you restart the server is good. We could
> also consider adding a step to the process that allows them to do the
> restart at that point, schedule a restart at a latter time, or just have
> the message.
>
>
>     Option 2: make it viewable only.
>
>     So option 2 is clearly the safest option, but has a drawback that
>     people
>     can't use the console to specify this configuration, they'd have to
>     crack open the .xml and edit that.
>
>     Option 1 gives people a fancy editor over standalone.xml / domain.xml
>     but does have the disadvantage that the specified values don't get
>     applied until the restart is done.
>
>     How do we generally handle this? Obviously, the best thing to do is
>     change the behaviour so that the restart isn't needed by sometimes this
>     isn't the highest priority within the realm of time constraints...
>
> If we can change the behavior to not require a restart that would be
> preferable. If we could come up with a list of changes that do require a
> restart, we could do two things with it. We could document it in the
> administration guide, but we could also track it via Andiamo, and make
> determinations on which things would be the most beneficial to invest in
> making it that we don't have to do a restart, and change things over
> time (release to release).
>

Sounds good.

> Andy
>
>
>     Cheers,
>
>     David
>     _______________________________________________
>     jboss-as7-dev mailing list
>     jboss-as7-dev at lists.jboss.org
>     https://lists.jboss.org/mailman/listinfo/jboss-as7-dev
>
>
>
>
> _______________________________________________
> jboss-as7-dev mailing list
> jboss-as7-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/jboss-as7-dev


-- 
Brian Stansberry
Principal Software Engineer
JBoss by Red Hat