Solr Upgrade Notes
The following notes describe changes to Solr in recent releases that you should be aware of before upgrading.
These notes highlight the important changes that may impact the largest number of implementations. It is not a comprehensive list of all changes to Solr in any release.
When planning your Solr upgrade, consider the customizations to
your system and review the
file found in your Solr package.
That file includes all the changes and updates
that may affect your existing implementation.
Detailed steps for upgrading a Solr cluster are in the section Upgrading a Solr Cluster.
Zookeeper Credentials support now follows a new paradigm.
Old classes, such as
VMParamsSingleSetCredentialsDigestZkCredentialsProvider, are deprecated but still supported until at least
Users are encouraged to upgrade to the non-deprecated classes before the next major version release.
Please refer to deployment-guide:zookeeper-access-control.adoc#solr-to-zookeeper-acls-workflow for more information.
Upgrading to 9.0 from 8.x Releases
The upgrade from 8.x to Solr 9.0 introduces several major changes that you should be aware of before upgrading. These changes are described in the section Major Changes in Solr 9. It’s strongly recommended that you thoroughly review that section before starting your upgrade.
If you run in SolrCloud mode and use SolrJ’s
|Rolling upgrades from Solr 8 to Solr 9 require first upgrading the cluster to version 8.7 or newer.|
Upgrading from Pre-8.x Versions
Users upgrading from versions prior to 8.x are strongly encouraged to consult
CHANGES.txt for the details of all changes since the version they are upgrading from.
The upgrade from 7.x to 8.0 introduced several major changes that you should be aware of before upgrading. Please do a thorough review of the section Major Changes in Solr 8 before starting your upgrade.
A summary of the significant changes between Solr 6.x and Solr 7.0 is in the section Major Changes in Solr 7.