Using a different JRE to the one installed

[Julian Halliwell]

We like to keep our JREs up to date with the latest security patches
and we find this easiest to just have one JRE per server and point to
it using a JAVA_HOME environment variable (this is on Windows).

However the advice for FR seems to be to replace the bundled JRE with
a *copy* of the updated JRE:

[FRS-358] How to upgrade the jre for FRAM / Instance Manager
https://www.fusion-reactor.com/support/kb/frs-358/

I've just updated FR to the latest version and noticed the included
JRE is already out of date. Just to see what would happen, I simply
deleted the JRE folder inside the FR installation directory.

FR started up fine. There doesn't seem to be a way of confirming which
JRE FR is using, but I'm assuming it's using the one at JAVA_HOME.

1) Could someone confirm that this is expected behaviour?
2) If so, would it be an idea to document this as the best way of
upgrading the JRE rather than copying?
3) Could the JRE version currently in use be stated on the About
FusionReactor screen?

Thanks
Julian Halliwell

[eleni_grosdouli]

Hi Julian,

When you say "Just to see what would happen, I simply deleted the JRE folder inside the FR installation directory. FR started up fine.", do you mean the FusionReactor Instance or the FRAM instance? FRAM uses its own JRE that is listed inside the FusionReactor directory while the application server will use the JAVA_HOME that you have specified on your machine. The technote provides instructions on how you can update the JRE that FRAM uses only.

In case you are going to delete the JRE folder of the FusionReactor directory, while the JAVA_HOME variable is set, FRAM will use the JAVA_HOME variable. The same situation occurs when you are using the "FusionReactor (no JRE) (includes the FR Admin Console)" installer. In that situation, you need to have a JAVA_HOME variable set up in order for the FRAM instance to start.

With regards to the third question, you have the ability to see the Java version that your FusionReactor instances is using by navigating to the following page: http:// IP ADDRESS:PORT/fusionreactor/findex.htm?p=env. However, I will discuss the possibility of adding this information to the About page with the development team.

Let me know if you have further questions.

Eleni

[Julian Halliwell]

Hi Eleni

On 10 October 2016 at 10:23, eleni_grosdouli <eleni.g...@gmail.com> wrote:
> When you say "Just to see what would happen, I simply deleted the JRE folder
> inside the FR installation directory. FR started up fine.", do you mean the
> FusionReactor Instance or the FRAM instance?

I mean the FRAM instance.

> FRAM uses its own JRE that is
> listed inside the FusionReactor directory while the application server will
> use the JAVA_HOME that you have specified on your machine. The technote
> provides instructions on how you can update the JRE that FRAM uses only.

Yes I understand that. My point is that copying a new JRE to the FR
JRE folder apparently isn't the only way of updating it and perhaps
your technote should mention that.

> In case you are going to delete the JRE folder of the FusionReactor
> directory, while the JAVA_HOME variable is set, FRAM will use the JAVA_HOME
> variable.

OK, that's what I assumed is happening. To my mind this is a better
way of keeping the JRE up to date.

The same situation occurs when you are using the "FusionReactor
> (no JRE) (includes the FR Admin Console)" installer. In that situation, you
> need to have a JAVA_HOME variable set up in order for the FRAM instance to
> start.

OK, perhaps I should use this instead of the main installer when
updating FR? Is that possible or is this only for fresh installs?

> With regards to the third question, you have the ability to see the Java
> version that your FusionReactor instances is using by navigating to the
> following page: http:// IP ADDRESS:PORT/fusionreactor/findex.htm?p=env.
> However, I will discuss the possibility of adding this information to the
> About page with the development team.

Thanks. Is that page linked from anywhere within FR? If it there's an
obvious link then maybe it doesn't need to be on the About page, but I
couldn't find it.

Cheers
Julian.

[eleni_grosdouli]

Hi Julian,

This page is mainly used from ours developers and that's the reason why you haven't been able to locate it in the documentation. However, I believe that we can do something about that and add the java version in the About page as it will be useful for other users as well!

With regards to the "FusionReactor (no JRE) (includes the FR Admin Console)", it would be more useful if that option was used for a fresh install because now you have used the full installer and in case you want to update your FRAM instance to the latest version you will have to run the latest .exe file.

Hope that helps!

Eleni

[Julian Halliwell]

Thanks, Eleni, that is helpful.
Julian.

[Julian Halliwell]

Hi Eleni

Just a follow-up to make clear that what would be helpful would be to
verify the JRE version FR itself is using. The "env" page you mention
shows what the monitored application instance is using. In my case
that's Lucee and that already confirms the JRE version in its admin
UI.

Cheers

Julian.

On 10 October 2016 at 11:09, eleni_grosdouli <eleni.g...@gmail.com> wrote:

> This page is mainly used from ours developers and that's the reason why you
> haven't been able to locate it in the documentation. However, I believe that
> we can do something about that and add the java version in the About page as
> it will be useful for other users as well!
>

>>[I wrote]

>> Thanks. Is that page linked from anywhere within FR? If it there's an
>> obvious link then maybe it doesn't need to be on the About page, but I
>> couldn't find it.
>>

>[Eleni wrote]

[eleni_grosdouli]

Hi Julian,

Thanks for the follow-up! I will discuss your idea with the development team and I will let you know!

Eleni