anchor.diff:  * JaegerTracerConfigurator no longer recognizes any configuration in solr.xml.
     It is now completely configured via System properties and/or Environment variables as documented by Jaeger.
   
  -=== Schema Changes in 9
  +=== Schema Changes
   
   * `LegacyBM25SimilarityFactory` has been removed.
   
  -=== Authentication & Security Changes in Solr 9
  -
  -* BasicAuthPlugin property 'blockUnknown' now defaults to 'true'. This change is backward incompatible. If you need the pre-9.0 default behavior, you need to explicitly set 'blockUnknown':'false' in security.json.
  +* SOLR-13593 SOLR-13690 SOLR-13691: Allow to look up analyzer components by their SPI names in field type configuration.
  +
  +=== Authentication & Security Changes
  +
  +* The property `blockUnknown` in the BasicAuthPlugin and the JWTAuthPlugin now defaults to `true`.
  +This change is backward incompatible.
  +If you need the pre-9.0 default behavior, you need to explicitly set `blockUnknown:false` in `security.json`.
   
   * The allow-list defining allowed URLs for the `shards` parameter is not in the `shardHandler` configuration anymore. It is defined by the `allowUrls` top-level property of the `solr.xml` file. For more information, see <<configuring-solr-xml.adoc#allow-urls, Format of solr.allowUrls>> documentation.
  +
  +* SOLR-13985: Solr's Jetty now binds to localhost network interface by default for better out of the box security.
  +Administrators that need Solr exposed more broadly can change the SOLR_JETTY_HOST property in their Solr include (solr.in.sh/solr.in.cmd) file.
  +
  +* SOLR-14147: Solr now runs with the java security manager enabled by default. Administrators that need to run Solr with Hadoop will need to disable this feature by setting SOLR_SECURITY_MANAGER_ENABLED=false in the environment or in one of the Solr init scripts. Other features in Solr could also break. (Robert Muir, marcussorealheis)
  +
  +* SOLR-14118: Solr embedded zookeeper only binds to localhost by default.
  +This embedded zookeeper should not be used in production.
  +If you rely upon the previous behavior, then you can change the clientPortAddress in solr/server/solr/zoo.cfg
  +
  +=== Contrib Changes
  +
  +* SOLR-14067: `StatelessScriptUpdateProcessorFactory` moved to `contrib/scripting` package instead of shipping as part of Solr, due to security concerns.
  +Renamed to ScriptUpdateProcessorFactory for simpler name.
  +
  +* SOLR-15121: `XSLTResponseWriter` moved to `contrib/scripting` package instead
  +of shipping as part of Solr, due to security concerns.
  +
  +* SOLR-14926: `contrib/clustering` back and rewritten
  +
  +* SOLR-14912: Cleaned up solr-extraction contrib to produce solr-extraction-* jar (instead of solr-cell-*). (Dawid Weiss)
  +
  +== Deprecations & Removed Features
  +
  +The following list of features have been permanently removed from Solr:
  +
  +* SOLR-14656: Autoscaling framework removed.
  +This includes:
  +** Autoscaling, policy, triggers etc.
  +** withCollection handling (SOLR-14964)
  +** UTILIZENODE command
  +** Sim framework
  +** Suggestions tab in UI
  +** Reference guide pages for autoscaling
  +** autoAddReplicas feature
  +
  +* SOLR-14783: Data Import Handler (DIH) has been removed from Solr.
  +The community package is available at: https://github.com/rohitbemax/dataimporthandler
  +
  +* SOLR-14792: VelocityResponseWriter has been removed from Solr.
  +This encompasses all previous included `/browse` and `wt=velocity` examples.
  +This feature has been migrated to an installable package at https://github.com/erikhatcher/solr-velocity
  +
  +* SOLR-13817: Legacy SolrCache implementations (LRUCache, LFUCache, FastLRUCache) have been removed.
  +Users have to modify their existing configurations to use CaffeineCache instead. (ab)
  +
  +* CDCR
  +
  +* Storing indexes and backups in HDFS
  +
  +* Solr's blob store
  +** SOLR-14654: plugins cannot be loaded using "runtimeLib=true" option. Use the package manager to use and load plugins
  +
  +* Metrics History
  +
  +* SOLR-15470: The binary distribution no longer contains test-framework jars.
  +
  +* SOLR-15203: Remove the deprecated `jwkUrl` in favour of `jwksUrl` when configuring JWT authentication.
  +
  +* SOLR-12847: maxShardsPerNode parameter has been removed because it was broken and inconsistent with other replica placement strategies.
  +Other relevant placement strategies should be used instead, such as autoscaling policy or rules-based placement.
  +
  +* SOLR-14092: Deprecated BlockJoinFacetComponent and BlockJoinDocSetFacetComponent are removed.
  +Users are encouraged to migrate to uniqueBlock() in JSON Facet API.  (Mikhail Khludnev)
  +
  +* SOLR-13596: Deprecated GroupingSpecification methods are removed.
  +
  +* SOLR-11266: default Content-Type override for JSONResponseWriter from `_default` configSet is removed.
  +Example has been provided in `sample_techproducts_configs` to override content-type.
  +
  +* `min_rf` deprecated in 7.x
  
positive.code: 
  = Major Changes in Solr 9
  // Licensed to the Apache Software Foundation (ASF) under one
  // or more contributor license agreements.  See the NOTICE file
  
negative.code: 
  A thorough review of the list in Major Changes in Earlier 8.x Versions as well as the {solr-javadocs}/changes//Changes.html[CHANGES.txt] in your Solr instance will help you plan your migration to Solr 9.
  
  === Upgrade Prerequisites
  
  * LUCENE-8738: Move to Java 11 as minimum Java version.
  
  * Upgrade all collections in `stateFormat=1` to `stateFormat=2` *before* upgrading to Solr 9, as Solr 9 does not support the older format and no longer supports migrating collections from the older format to the current format (previously known as stateFormat=2).
  Upgrade is to be done using Collection API MIGRATESTATEFORMAT action using a previous version of Solr.
  See for example https://solr.apache.org/guide/8_8/cluster-node-management.html#migratestateforma[Solr 8.8 Ref Guide].
  // Can't link directly to .adoc file, need to link to 8.something ref guide as MIGRATESTATEFORMAT no longer exists in 9.0.
  
  * SOLR-12823: Remove `/clusterstate.json` support, i.e., support for collections created with `stateFormat=1` as well as support for Collection API MIGRATESTATEFORMAT action.
  Also removes support for cluster property `legacyCloud` (as if always false now).
  
  * If you're using a SolrJ CloudClient to connect to your Solr cluster, you must be using SolrJ version 8.10 or higher (8.x) when upgrading your SolrCloud from 8.x to 9.x.
  Otherwise, SolrJ will not be able to connect to the cluster once it has upgraded to Solr 9.
  