Exception while querying Solr:
array(4 items) extKey => 'solr' (4 chars) msg => 'Exception while querying Solr' (29 chars) level => 'error' (5 chars) data => array(4 items) exception => 'ApacheSolrForTypo3\Solr\System\Solr\SolrCommunicationException: Invalid quer
y. Solr returned an error: 404 Not Found in /var/www/production.ipb-halle.de
/releases/18/vendor/apache-solr-for-typo3/solr/Classes/System/Solr/Service/S
olrReadService.php:98 Stack trace: #0 /var/www/production.ipb-halle.de/relea
ses/18/vendor/apache-solr-for-typo3/solr/Classes/System/Solr/Service/SolrRea
dService.php(51): ApacheSolrForTypo3\Solr\System\Solr\Service\SolrReadServic
e->handleErrorResponse() #1 /var/www/production.ipb-halle.de/releases/18/ven
dor/apache-solr-for-typo3/solr/Classes/Search.php(118): ApacheSolrForTypo3\S
olr\System\Solr\Service\SolrReadService->search() #2 /var/www/production.ipb
-halle.de/releases/18/vendor/apache-solr-for-typo3/solr/Classes/Domain/Searc
h/ResultSet/SearchResultSetService.php(221): ApacheSolrForTypo3\Solr\Search-
>search() #3 /var/www/production.ipb-halle.de/releases/18/vendor/apache-solr
-for-typo3/solr/Classes/Domain/Search/ResultSet/SearchResultSetService.php(1
31): ApacheSolrForTypo3\Solr\Domain\Search\ResultSet\SearchResultSetService-
>doASearch() #4 /var/www/production.ipb-halle.de/releases/18/vendor/apache-s
olr-for-typo3/solr/Classes/Controller/SearchController.php(112): ApacheSolrF
orTypo3\Solr\Domain\Search\ResultSet\SearchResultSetService->search() #5 /va
r/www/production.ipb-halle.de/releases/18/vendor/typo3/cms-extbase/Classes/M
vc/Controller/ActionController.php(477): ApacheSolrForTypo3\Solr\Controller\
SearchController->resultsAction() #6 /var/www/production.ipb-halle.de/releas
es/18/vendor/typo3/cms-extbase/Classes/Mvc/Controller/ActionController.php(3
94): TYPO3\CMS\Extbase\Mvc\Controller\ActionController->callActionMethod() #
7 /var/www/production.ipb-halle.de/releases/18/vendor/typo3/cms-extbase/Clas
ses/Mvc/Dispatcher.php(68): TYPO3\CMS\Extbase\Mvc\Controller\ActionControlle
r->processRequest() #8 /var/www/production.ipb-halle.de/releases/18/vendor/t
ypo3/cms-extbase/Classes/Core/Bootstrap.php(168): TYPO3\CMS\Extbase\Mvc\Disp
atcher->dispatch() #9 /v...' (19369 chars) query => array(10 items)