This is an automated email from the ASF dual-hosted git repository.
ctargett pushed a commit to branch main
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The following commit(s) were added to refs/heads/main by this push:
new c3be04d SOLR-15757: 1st pass at some light organization structure
c3be04d is described below
commit c3be04d66922dbfc2cbbcc08f63b3b4fd15dea59
Author: Cassandra Targett <[email protected]>
AuthorDate: Wed Nov 3 13:30:37 2021 -0500
SOLR-15757: 1st pass at some light organization structure
---
.../src/major-changes-in-solr-9.adoc | 276 +++++++++++----------
1 file changed, 143 insertions(+), 133 deletions(-)
diff --git a/solr/solr-ref-guide/src/major-changes-in-solr-9.adoc
b/solr/solr-ref-guide/src/major-changes-in-solr-9.adoc
index a9d2c6e..cd8c41e 100644
--- a/solr/solr-ref-guide/src/major-changes-in-solr-9.adoc
+++ b/solr/solr-ref-guide/src/major-changes-in-solr-9.adoc
@@ -1,4 +1,3 @@
-
= Major Changes in Solr 9
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
@@ -29,175 +28,110 @@ You should also consider all changes that have been made
to Solr in any version
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.
-== Solr 9.0
-
-_(raw; not yet edited)_
-
-* SOLR-14912: Cleaned up solr-extraction contrib to produce solr-extraction-*
jar
- (instead of solr-cell-*). (Dawid Weiss)
+=== Upgrade Prerequisites
* LUCENE-8738: Move to Java 11 as minimum Java version.
- (Adrien Grand, Uwe Schindler)
-
-* SOLR-13671: Allow 'var' keyword in Java sources
-* SOLR-12055 introduces async logging by default. There's a small window where
log messages may be lost
- in the event of some hard crash. Switch back to synchronous logging if this
is unacceptable, see
- see comments in the log4j2 configuration files (log4j2.xml by default).
-
-* SOLR-12891: MacroExpander will no longer will expand URL parameters inside
of the 'expr' parameter (used by streaming
- expressions) Additionally, users are advised to use the 'InjectionDefense'
class when constructing streaming
- expressions that include user supplied data to avoid risks similar to SQL
injection. The legacy behavior of
- expanding the 'expr' parameter can be reinstated with
-DStreamingExpressionMacros=true passed to the JVM at startup
- (Gus Heck).
-
-* SOLR-13324: URLClassifyProcessor#getCanonicalUrl now throws
MalformedURLException rather than hiding it. Although the
- present code is unlikely to produce such an exception it may be possible in
future changes or in subclasses.
- Currently this change should only effect compatibility of custom code
overriding this method (Gus Heck).
+* 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-13323: The unused package org.apache.solr.internal.csv.writer and
associated classes/tests that were easily
- confused with but not used by org.apache.solr.response.CSVWriter (or any
other code) have been removed (Gus Heck)
+* 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).
-* SOLR-7530: TermsComponent's JSON response format was changed so that "terms"
property carries per field arrays by default
- regardless of distrib, terms.list, terms.ttf parameters. This affects JSON
based response format but not others
- (Munendra S N, Mikhail Khludnev)
+* 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.
+Once you have upgraded all Solr clusters that the client is connecting to, you
can upgrade the SolrJ client to 9.x.
-* SOLR-13596: Deprecated GroupingSpecification methods are removed. (Munendra
S N)
+* If you're using Solr in standalone mode with the
<<query-elevation-component.adoc#,Query Elevation Component>> with it's
elevation file in the data directory, you'll have to move it to the
<<config-sets.adoc#,Configset>> instead.
+The only reason QEC supported the data directory was to support loading its
changes on a commit instead of a more expensive core reload.
+That feature now works from the configset dir too.
+SolrCloud doesn't support that but may sometime.
-* SOLR-13649: Property 'blockUnknown' of BasicAuthPlugin and JWTAuthPlugin now
defaults to 'true'. This change is backward
- incompatible. To achieve the previous default behavior, explicitly set
'blockUnknown':'false' in security.json
- (marcussorealheis, janhoy, shalin)
+=== Rolling Upgrades
-* 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. (Ishan
Chattopadhyaya, Munendra S N, Gus Heck)
+* SOLR-14702: All references to "master" and "slave" were replaced in the code
with "leader" and "follower".
+This includes API calls for the replication handler and metrics.
+For rolling upgrades into 9.0, you need to be on Solr version 8.7 or greater.
Some metrics also changed, alerts and monitors on Solr KPIs that mention
"master" or "slave" will also now be "leader" and "follower"
-* SOLR-13593 SOLR-13690 SOLR-13691: Allow to look up analyzer components by
their SPI names in field type configuration. (Tomoko Uchida)
+=== Reindexing After Upgrade
-* SOLR-13854, SOLR-13858: SolrMetricProducer / SolrInfoBean APIs have changed
and third-party components that implement these APIs need to be updated. (ab)
+In Solr 8, it's possible to add docValues to a schema without re-indexing via
`UninvertDocValuesMergePolicy`, an advanced/expert utility.
+Due to changes in Lucene 9, that isn't possible any more; the component was
removed.
+If re-indexing is too onerous, use this mechanism in Solr 8.
-* SOLR-13783: In situations where a NamedList must be output as plain text,
commas between key-value pairs will now be
- followed by a space (e.g., {shape=square, color=yellow} rather than
{shape=square,color=yellow}) for consistency with
- other java.util.Map implementations based on AbstractMap (Chris Hennick).
+== Solr 9.0 Raw Notes
-* SOLR-13817: Legacy SolrCache implementations (LRUCache, LFUCache,
FastLRUCache) have been removed.
- Users have to modify their existing configurations to use CaffeineCache
instead. (ab)
+_(raw; not yet edited)_
-* SOLR-14092: Deprecated BlockJoinFacetComponent and
BlockJoinDocSetFacetComponent are removed
- Users are encouraged to migrate to uniqueBlock() in JSON Facet API.
(Mikhail Khludnev)
-* 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. (Jason Gerlowski, David Smiley, Robert Muir)
-
-* 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-13671: Allow 'var' keyword in Java sources
-* 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 (Robert Muir)
+* SOLR-12055 introduces async logging by default. There's a small window where
log messages may be lost in the event of some hard crash.
+Switch back to synchronous logging if this is unacceptable, see comments in
the log4j2 configuration files (log4j2.xml by default).
-* SOLR-11725: JSON aggregations uses corrected sample formula to compute
standard deviation and variance.
- The computation of stdDev and variance in JSON aggregation is same as
StatsComponent. (hossman, Munendra S N, yonik)
+* SOLR-13323: The unused package org.apache.solr.internal.csv.writer and
associated classes/tests that were easily confused with but not used by
org.apache.solr.response.CSVWriter (or any other code) have been removed
-* SOLR-14012: unique and hll aggregations always returns long value
irrespective of standalone or solcloud
- (Munendra S N, hossman)
+* SOLR-13854, SOLR-13858: SolrMetricProducer / SolrInfoBean APIs have changed
and third-party components that implement these APIs need to be updated.
* SOLR-14344: Remove Deprecated HttpSolrClient.RemoteSolrException and
HttpSolrClient.RemoteExcecutionException.
- All the usages are replaced by BaseHttpSolrClient.RemoteSolrException and
BaseHttpSolrClient.RemoteExcecutionException.
- (Munendra S N)
+All the usages are replaced by BaseHttpSolrClient.RemoteSolrException and
BaseHttpSolrClient.RemoteExcecutionException.
-* SOLR-12720: To change the auto add replica wait period modify the `waitFor`
attribute of the `.auto_add_replicas` trigger.
- (marcussorealheis, shalin)
-
-* SOLR-11775: Return long value for facet count in Json Facet module
irrespective of number of shards (hossman, Munendra S N)
+* SOLR-15409: Zookeeper client libraries upgraded to 3.7.0, which may not be
compatible with your existing server installations
-* 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).
-* 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
+== New Features & Enhancements
-* SOLR-14702: All references to "master" and "slave" were replaced in the code
with "leader"
- and "follower". This includes API calls for the replication handler and
metrics. For rolling
- upgrades into 9.0, you need to be on Solr version 8.7 or greater. Some
metrics also changed, alerts and
- monitors on Solr KPIs that mention "master" or "slave" will also now be
"leader" and "follower"
+* Replica placement plugins
-* SOLR-14783: Data Import Handler (DIH) has been removed from Solr. The
community package is available at:
https://github.com/rohitbemax/dataimporthandler (Alexandre Rafalovitch)
+* Rate limiting and task management
-* 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
+* Certificate Auth Plugin
-* SOLR-14510: The `writeStartDocumentList` in `TextResponseWriter` now
receives an extra boolean parameter representing the "exactness" of the
numFound value (exact vs approximation).
- Any custom response writer extending `TextResponseWriter` will need to
implement this abstract method now (instead previous with the same name but
without the new boolean parameter).
+* SQL Query interface in UI
-* SOLR-14036: Implicit /terms handler now returns terms across all shards in
SolrCloud instead of only the local core. Users/apps may be assuming the old
behavior. A request can be modified via the standard distrib=false param to
only use the local core receiving the request.
+== Configuration and Default Parameter Changes
-* 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-7530: TermsComponent's JSON response format was changed so that "terms"
property carries per field arrays by default regardless of distrib, terms.list,
terms.ttf parameters.
+This affects JSON based response format but not others
-* SOLR-14654: plugins cannot be loaded using "runtimeLib=true" option. Use the
package manager to use and load plugins
+* SOLR-14036: Implicit /terms handler now returns terms across all shards in
SolrCloud instead of only the local core.
+Users/apps may be assuming the old behavior.
+A request can be modified via the standard distrib=false param to only use the
local core receiving the request.
-* SOLR-14972: The default port of prometheus exporter has changed from 9983 to
8989, so you may need to adjust your configuration after upgrade.
+* SOLR-13783: In situations where a NamedList must be output as plain text,
commas between key-value pairs will now be followed by a space (e.g.,
{shape=square, color=yellow} rather than {shape=square,color=yellow}) for
consistency with other `java.util.Map` implementations based on `AbstractMap`.
-* 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-11725: JSON aggregations uses corrected sample formula to compute
standard deviation and variance.
+The computation of stdDev and variance in JSON aggregation is same as
StatsComponent.
-* SOLR-15121: XSLTResponseWriter moved to /contrib/scripting/ package instead
- of shipping as part of Solr, due to security concerns.
+* SOLR-14012: unique and hll aggregations always returns long value
irrespective of standalone or solcloud
-* SOLR-15203: Remove the deprecated `jwkUrl` in favour of `jwksUrl` when
configuring JWT authentication.
+* SOLR-11775: Return long value for facet count in Json Facet module
irrespective of number of shards
* SOLR-15276: V2 API call to look up async request status restful style of
"/cluster/command-status/1000" instead of
"/cluster/command-status?requestid=1000".
-* SOLR-15409: Zookeeper client libraries upgraded to 3.7.0, which may not be
compatible with your existing server installations
-
-* SOLR-15470: The binary distribution no longer contains test-framework jars.
+* SOLR-14972: The default port of prometheus exporter has changed from 9983 to
8989, so you may need to adjust your configuration after upgrade.
* SOLR-15471: The language identification "whitelist" configuration is now an
"allowlist" to better convey the meaning of the property
-=== Upgrade Prerequisites in Solr 9
+* SOLR-12891: MacroExpander will no longer will expand URL parameters inside
of the 'expr' parameter (used by streaming expressions).
+Additionally, users are advised to use the 'InjectionDefense' class when
constructing streaming expressions that include user supplied data to avoid
risks similar to SQL injection.
+The legacy behavior of expanding the 'expr' parameter can be reinstated with
-DStreamingExpressionMacros=true passed to the JVM at startup
-* 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-13324: URLClassifyProcessor#getCanonicalUrl now throws
MalformedURLException rather than hiding it.
+Although the present code is unlikely to produce such an exception it may be
possible in future changes or in subclasses.
+Currently this change should only effect compatibility of custom code
overriding this method.
-* 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.
-Once you have upgraded all Solr clusters that the client is connecting to, you
can upgrade the SolrJ client to 9.x.
-
-* If you're using Solr in standalone mode with the
<<query-elevation-component.adoc#,Query Elevation Component>> with it's
elevation file in the data directory, you'll have to move it to the
<<config-sets.adoc#,Configset>> instead.
-The only reason QEC supported the data directory was to support loading its
changes on a commit instead of a more expensive core reload.
-That feature now works from the configset dir too.
-SolrCloud doesn't support that but may sometime.
-
-=== Rolling Upgrades with Solr 9
-
-=== Reindexing After Upgrades in Solr 9
-
-In Solr 8, it's possible to add docValues to a schema without re-indexing via
UninvertDocValuesMergePolicy, an advanced/expert utility.
-Due to changes in Lucene 9, that isn't possible any more; the component was
removed.
-If re-indexing is too onerous, use this mechanism in Solr 8.
-
-== New Features & Enhancements in Solr 9
-
-== Configuration and Default Parameter Changes in Solr 9
+* SOLR-14510: The `writeStartDocumentList` in `TextResponseWriter` now
receives an extra boolean parameter representing the "exactness" of the
`numFound` value (exact vs approximation).
+Any custom response writer extending `TextResponseWriter` will need to
implement this abstract method now (instead previous with the same name but
without the new boolean parameter).
=== solr.xml maxBooleanClauses now enforced recursively
Lucene 9.0 has additional safety checks over previous versions that impact how
the `solr.xml` global
`<<configuring-solr-xml#global-maxbooleanclauses,maxBooleanClauses>>` option is
enforced.
-In previous versios of Solr, this option was a hard limit on the number of
clauses in any `BooleanQuery` object - but it was only enforced for the
_direct_ clauses. Starting with Solr 9, this global limit is now also enforced
against the total number of clauses in a _nested_ query structure.
+In previous versios of Solr, this option was a hard limit on the number of
clauses in any `BooleanQuery` object - but it was only enforced for the
_direct_ clauses.
+Starting with Solr 9, this global limit is now also enforced against the total
number of clauses in a _nested_ query structure.
Users who upgrade from prior versions of Solr may find that some requests
involving complex internal query structures (Example: long query strings using
`edismax` with many `qf` and `pf` fields that include query time synonym
expansion) which worked in the past now hit this limit and fail.
@@ -205,17 +139,18 @@ User's in this situation are advised to consider the
complexity f their queries/
=== Log4J configuration & Solr MDC values
-link:http://www.slf4j.org/apidocs/org/slf4j/MDC.html[MDC] values that Solr
sets for use by Logging calls (such as the collection name, shard name, replica
name, etc...) have been modified to now be "bare" values, with out the special
single character prefixes that were included in past version. For example: In
8.x Log messages for a collection named "gettingstarted" would have an MDC
value with a key `collection` mapped to a value of `c:gettingstarted`, in 9.x
the value will simply be ` [...]
+link:http://www.slf4j.org/apidocs/org/slf4j/MDC.html[MDC] values that Solr
sets for use by Logging calls (such as the collection name, shard name, replica
name, etc...) have been modified to now be "bare" values, with out the special
single character prefixes that were included in past version.
+For example: In 8.x Log messages for a collection named "gettingstarted" would
have an MDC value with a key `collection` mapped to a value of
`c:gettingstarted`, in 9.x the value will simply be `gettingstarted`.
-Solr's default `log4j2.xml` configuration file has been modified to prepend
these same prefixes to MDC values when included in Log messages as part of the
`<PatternLayout/>`. Users who have custom logging configurations that wish to
ensure Solr 9.x logs are consistently formatted after upgrading will need to
make similar changes to their logging configuration files. See
link:https://issues.apache.org/jira/browse/SOLR-15630[SOLR-15630] for more
details.
+Solr's default `log4j2.xml` configuration file has been modified to prepend
these same prefixes to MDC values when included in Log messages as part of the
`<PatternLayout/>`.
+Users who have custom logging configurations that wish to ensure Solr 9.x logs
are consistently formatted after upgrading will need to make similar changes to
their logging configuration files. See
link:https://issues.apache.org/jira/browse/SOLR-15630[SOLR-15630] for more
details.
=== base_url removed from stored state
-If you're able to upgrade SolrJ to 8.8.x for all of your client applications,
then you can set `-Dsolr.storeBaseUrl=false` (introduced in Solr 8.8.1)
-to better align the stored state in Zookeeper with future versions of Solr; as
of Solr 9.x, the `base_url` will no longer be
-persisted in stored state. However, if you are not able to upgrade SolrJ to
8.8.x for all client applications, then you should
-set `-Dsolr.storeBaseUrl=true` so that Solr will continue to store the
`base_url` in Zookeeper. For background, see: SOLR-12182 and SOLR-15145.
+If you're able to upgrade SolrJ to 8.8.x for all of your client applications,
then you can set `-Dsolr.storeBaseUrl=false` (introduced in Solr 8.8.1) to
better align the stored state in Zookeeper with future versions of Solr; as of
Solr 9.x, the `base_url` will no longer be persisted in stored state.
+However, if you are not able to upgrade SolrJ to 8.8.x for all client
applications, then you should set `-Dsolr.storeBaseUrl=true` so that Solr will
continue to store the `base_url` in Zookeeper.
+For background, see: SOLR-12182 and SOLR-15145.
Support for the `solr.storeBaseUrl` system property will be removed in Solr
10.x and `base_url` will no longer be stored.
@@ -227,12 +162,87 @@ What percentage of them get reported to a tracing server
is up to you.
* 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
+* SOLR-13593 SOLR-13690 SOLR-13691: Allow to look up analyzer components by
their SPI names in field type configuration.
+
+=== Authentication & Security Changes
-* 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.
+* 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
