update java for DST on-the-fly

[Marc Ahrendt]

is it possible to update a java install for DST without having to restart java processes?

basically can "tzupdater.jar" be executed against java while processes are running? ...and then instead of restarting all the java processes maybe send a HUP signal or something to them to refresh them of these TZ updates?

yes, i know its documented to stop all java processes before using "tzupdater.jar" ...just curious if others have found another way to update without killing the processes or killing the processes after doing the update

[Rick Garland]

With the tzupdater for java1.3 you can do on the fly. Use the "-s" option.

Been doing java1.4 on quiet systems.

[Marc Ahrendt]

more information:

1) i have ben addressing 1.4.x installs
2) i was able to execute "tzupdater.jar" successfully while java processes were running
3) on a few servers, as an experiment, i did not restart the java processes. my assumption is that most likely they will correctly do DST on march 11 since basically only the DST rules have changed (.../lib/zi) and not how they are referenced by the java classes ...and we are still using a TZ that has not changed in name.
4) i think SUN to cover all environments has to tell users to stop java, update java, start java.

[Rick Garland]

There is a recent release of a tool that HP put out called 'dstivp'. This tool is unsupported. HP will do nothing to support.

The dstivp tool will run through the system and do checks on the OS patching, java updates, and some libraries.

The java checking is useful. Will identify the installed javas' on the system and report the version. It checks the DST info of the respective java version.

As an idea, you could run the tzupdater on java1.4 while live and then run this dstivp tool to see if the updates have been put in place and are recognized.

[Marc Ahrendt]

rick, i did use that utility (dstivp_11_v012.tar.gz) as you suggested and it tested fine ...i included it here for others to easily access.

also i tested the update by simply running ".../jre/bin/java -jar tzupdater.jar -V" afterwards

bottom line is that for our Java environment it was possible to update on-the-fly without impacting production (no need for killing java in advance) and seemingly allow current running java processes to see the new TZ vaules

[Alzhy]

Is there a similar tool available (dstivp_11_v012.tar.gz) for Solaris? Where did this tool come from?

[Dennis Handly]

>Nelson: Is there a similar tool available for Solaris?

While it might work for java, the aC++ parts are particular to HP-UX