Hi all,
I'm Kobi Ohayon, from RnD.
The mentioned limitation is indeed true, since in R81 we changed our indexing system (SOLR). So when upgrading to R81, old indexes will not survive and a re-index will be needed.
As a default, we've set the re-index to 1 days back (24 hours), but of course it can be changed to whatever number of days back you like. Please notice the following:
1. If you set the day to index to 60, and then you want to extend it to 90 or 120, already indexed log files will not be re-indexed again. We will skip those files and proceed with the older ones.
2. Offline indexing consumes a lot of CPU time, and might cause log queries to temporarily be unavailable.
3. When you set the re-index for X days back, make sure the maintenance configuration will not delete those indexes right when they created. And also make sure you have enough disk space in /var/log partition.
Thanks.