Difference between revisions of "HowTos/Working with JRE"

Revision as of 19:09, 21 November 2013

Common Notes

• According to Oracle license, scalix can't distribute JRE installation inside installer, you need to explicitly visit oracle site, download and install JRE
• In scalix v.12.0 JRE 1.5 and above is supported (except ldapsync known issue, that hopefully will be fixed in future versions Advanced omldapsync How-To
• In many systems like centos/rhel/oracle linux openjdk (opensource java implementation) is already included in distributive and can be installed using standard package installation procedure (yum, yast, etc.)
• we don't recommend using openjdk on high-load systems because it can cause potential slowdown, higher CPU/Memory usage and probably can cause unexpected errors. Of course for testing purposes or if you not want to deal with JRE customization, you can use openjdk implementaion, since it's well-known as stable platform
• in scalix v12.0 some scripts still have

How scalix installer determines JRE presence and version

Since v12.0, scalix installer tries to determine available java version in 2 steps

• it tries to execute "java -version" command. If it fails, installer assumes JRE is not available (even if you downloaded and installed jre from 3rd party location) - see next section
• it compares command output and tries to parse java version; if it fits installer requirements, java test is passed

How to install JRE

Starting from version 12.0, scalix doesn't try to find available java, it leans on system in this case (assuming "java" command can be executed). In general, there're 2 options

• if you installed openjdk, "java" command is already available and there won't be any unexpected issues
• if you downloaded and installed JRE from Oracle site, it's not enough to install it, you need to explicitly tell system what JRE to use. You can use jre configuration guide for centos for more details.