Upgrading the Elastic Stack perfectly documents the process to
upgrade ES from 5 to 6 when internal indices are present. However,
the rolling upgrade docs do not mention anything about internal indices.
This adds a warning in the rolling upgrade procedure, highlighting that
internal indices should be upgraded before the rolling upgrade procedure
can be started.
Tweak the upgrade instructions for moving from pre-6.3-with-x-pack to
post-6.3-default distribution. Specifically, you have to remove the
x-pack plugin before upgrading because 6.4 doesn't understand how to
remove it.
Relates to #34307
Since we disable allocation using persistent settings, we should be consistent and remove
the setting from the persistent storage. Otherwise an accidental restart will lead for shards
not being allocated.
Relates to #28757
debadair
Lisa Cawley
Albert Zaharovits
Nik Everett
Boaz Leskes