Error loading class 'solr.ICUCollationField' whilst setting up core

I was just encountering the ICUCollationField issue with Search API Solr 4.3.7 and Solr 9.8.0, and found the previous solutions did not work, but the following two solutions did work:

1. Either add the following line to /etc/default/solr.in.sh:
$SOLR_OPTS -Dsolr.sharedLib=/opt/solr/modules/analysis-extras/lib"

2. Or copy the contents of:
/opt/solr/modules/analysis-extras/lib
to
/opt/solr/server/solr-webapp/webapp/WEB-INF/lib

Hi, I have encountered the same issue with Search API Solr 4.3.7 and Solr 9.8.0. I found the following at the Logging page of Solr config;

WARN false

d8

SolrConfig

Configset references one or more <lib/> directives,&#8203; but <lib/> usage is disabled on this Solr node. Either remove all <lib/> tags from the relevant configset,&#8203; or <strong>enable use of this feature by setting 'solr.config.lib.enabled=true'</strong>

I have taken another solution and it works.
sudo vi /etc/default/solr.in.sh

SOLR_OPTS="$SOLR_OPTS -Dsolr.config.lib.enabled=true"

Major Changes in Solr 9.8: https://solr.apache.org/guide/solr/latest/upgrade-notes/major-changes-in-solr-9.html#solr-9-8

For people running solr in containers: This can be fixed by supplying module configuration via the SOLR_MODULES environment variable.

The following value loads all the modules referenced from solrconfig.xml currently shipped by Search API Solr module:

SOLR_MODULES=extraction,langid,ltr,analysis-extras

Hello!,

As says znerol, if you edit your docker-compose.yml and you add this to the file, the issue will be fixed:

solr:
image: wodby/solr:$SOLR_TAG
container_name: "${PROJECT_NAME}_solr"
environment:
SOLR_MODULES: extraction,langid,ltr,analysis-extra

The important part is "SOLR_MODULES:"

It will be neccesary restart the container

Hello!,

As says znerol, if you edit your docker-compose.yml and you add this to the file, the issue will be fixed:

solr:
image: wodby/solr:$SOLR_TAG
container_name: "${PROJECT_NAME}_solr"
environment:
SOLR_MODULES: extraction,langid,ltr,analysis-extras

The important part is "SOLR_MODULES:"

It will be neccesary restart the container

I encountered the same issue with DDEV while upgrading Solr from version 8 to 9.

To fix it, I had to add the following to docker-compose.solr.yaml:

services:
    solr:
        build:
            args:
               SOLR_BASE_IMAGE: ${SOLR_BASE_IMAGE:-solr:9}
          environment:
              - SOLR_MODULES=extraction,langid,ltr,analysis-extras,scripting

And in .ddev/solr/conf/solrconfig.xml, I had to update the XSLTResponseWriter class:

  - <queryResponseWriter name="xslt" class="solr.XSLTResponseWriter">
  + <queryResponseWriter name="xslt" class="solr.scripting.xslt.XSLTResponseWriter">

After these changes, all communication started working correctly.

Maybe it will help someone :)