Server error after Certbot certificate installation

Hi to all,
this is my installation:
Nextcloud 23.0.0.10
Ubuntu 18.04.6 LTS
Apache/2.4.29
mysql Ver 14.14 Distrib 5.7.36
PHP 7.4.27
Installation path: /var/www/nextcloud - permissions 755
Data: /var/www/nextcloud-data - permissions 770
These directories are owned by www-data:www-data

I have installed Nextcloud without problems and I was able to see installation page at http://nextcloud.mydomain.com.

Then I’ve installed Certbot certificate and… voilà; that’s the problem.
In /var/log/apache2/nextcloud.error I see:
[ssl:error] [pid 6281] [client xxx.xxx.xxx.xxx:48222] AH02042: rejecting client initiated renegotiation.

Request ID: MQOSQlSvb9ZDrdolxqpD

Please, can someone help me?
Thank you.

Hi,

Can you please post the error message in English here?

Sure!
INTERNAL SERVER ERROR
The server was unable to complete your request.
If this occurs again, send the following technical details to the server administrator.

More details can be found in the server log.
TECHNICAL DETAILS
Remote address: xxx.xxx.xxx.xxx
Request ID: MQOSQlSvb9ZDrdolxqpD

Ok?

Oh, this is just the generic error message then :sweat_smile:

Please post the latest error messages from the nextcloud.log (in your data directory) and maybe the webserver logs if they contain useful messages apart from the client renegotiation.
I guess, if the client renegotiation was related, you wouldn’t see the nextcloud page with the error message.

Attention: Please make sure to remove all sensitive information from the log entries, before posting them here.

Nextcloud.log is an huge file. I copy some latest messages:

,“line”:90,“function”:“getSharedWith”,“class”:“OC\Share20\Manager”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Config/MountProviderCollection.php",“line”:118,“function”:“getMountsForUser”,“class”:“OCA\Files_Sharing\MountProvider”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:429,“function”:“addMountForUser”,“class”:“OC\Files\Config\MountProviderCollection”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:354,“function”:“initMountPoints”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/private/legacy/OC_Util.php",“line”:326,“function”:“init”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/base.php",“line”:1029,“function”:“setupFS”,“class”:“OC_Util”,“type”:"::"},{“file”:"/var/www/nextcloud/index.php",“line”:36,“function”:“handleRequest”,“class”:“OC”,“type”:"::"}],“File”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/API/MySQL/ExceptionConverter.php",“Line”:114,“Previous”:{“Exception”:“Doctrine\DBAL\Driver\PDO\Exception”,“Message”:“SQLSTATE[HY001]: Memory allocation error: 1038 Out of sort memory, consider increasing server sort buffer size”,“Code”:1038,“Trace”:[{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php",“line”:94,“function”:“new”,“class”:“Doctrine\DBAL\Driver\PDO\Exception”,“type”:"::"},{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php",“line”:1057,“function”:“execute”,“class”:“Doctrine\DBAL\Driver\PDO\Statement”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/DB/Connection.php",“line”:236,“function”:“executeQuery”,“class”:“Doctrine\DBAL\Connection”,“type”:"->"},{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Query/QueryBuilder.php",“line”:345,“function”:“executeQuery”,“class”:“OC\DB\Connection”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php",“line”:287,“function”:“execute”,“class”:“Doctrine\DBAL\Query\QueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/vendor/artificial-owl/my-small-php-tools/lib/Db/Nextcloud/nc22/NC22ExtendedQueryBuilder.php",“line”:1340,“function”:“execute”,“class”:“OC\DB\QueryBuilder\QueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/vendor/artificial-owl/my-small-php-tools/lib/Db/Nextcloud/nc22/NC22ExtendedQueryBuilder.php",“line”:1276,“function”:“getRows”,“class”:“ArtificialOwl\MySmallPhpTools\Db\Nextcloud\nc22\NC22ExtendedQueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Db/ShareWrapperRequestBuilder.php",“line”:123,“function”:“asItems”,“class”:“ArtificialOwl\MySmallPhpTools\Db\Nextcloud\nc22\NC22ExtendedQueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Db/ShareWrapperRequest.php",“line”:339,“function”:“getItemsFromRequest”,“class”:“OCA\Circles\Db\ShareWrapperRequestBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Service/ShareWrapperService.php",“line”:180,“function”:“getSharedWith”,“class”:“OCA\Circles\Db\ShareWrapperRequest”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/ShareByCircleProvider.php",“line”:557,“function”:“getSharedWith”,“class”:“OCA\Circles\Service\ShareWrapperService”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Share20/Manager.php",“line”:1375,“function”:“getSharedWith”,“class”:“OCA\Circles\ShareByCircleProvider”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/files_sharing/lib/MountProvider.php",“line”:90,“function”:“getSharedWith”,“class”:“OC\Share20\Manager”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Config/MountProviderCollection.php",“line”:118,“function”:“getMountsForUser”,“class”:“OCA\Files_Sharing\MountProvider”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:429,“function”:“addMountForUser”,“class”:“OC\Files\Config\MountProviderCollection”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:354,“function”:“initMountPoints”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/private/legacy/OC_Util.php",“line”:326,“function”:“init”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/base.php",“line”:1029,“function”:“setupFS”,“class”:“OC_Util”,“type”:"::"},{“file”:"/var/www/nextcloud/index.php",“line”:36,“function”:“handleRequest”,“class”:“OC”,“type”:"::"}],“File”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Exception.php",“Line”:26,“Previous”:{“Exception”:“PDOException”,“Message”:“SQLSTATE[HY001]: Memory allocation error: 1038 Out of sort memory, consider increasing server sort buffer size”,“Code”:“HY001”,“Trace”:[{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php",“line”:92,“function”:“execute”,“class”:“PDOStatement”,“type”:"->"},{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php",“line”:1057,“function”:“execute”,“class”:“Doctrine\DBAL\Driver\PDO\Statement”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/DB/Connection.php",“line”:236,“function”:“executeQuery”,“class”:“Doctrine\DBAL\Connection”,“type”:"->"},{“file”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Query/QueryBuilder.php",“line”:345,“function”:“executeQuery”,“class”:“OC\DB\Connection”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php",“line”:287,“function”:“execute”,“class”:“Doctrine\DBAL\Query\QueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/vendor/artificial-owl/my-small-php-tools/lib/Db/Nextcloud/nc22/NC22ExtendedQueryBuilder.php",“line”:1340,“function”:“execute”,“class”:“OC\DB\QueryBuilder\QueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/vendor/artificial-owl/my-small-php-tools/lib/Db/Nextcloud/nc22/NC22ExtendedQueryBuilder.php",“line”:1276,“function”:“getRows”,“class”:“ArtificialOwl\MySmallPhpTools\Db\Nextcloud\nc22\NC22ExtendedQueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Db/ShareWrapperRequestBuilder.php",“line”:123,“function”:“asItems”,“class”:“ArtificialOwl\MySmallPhpTools\Db\Nextcloud\nc22\NC22ExtendedQueryBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Db/ShareWrapperRequest.php",“line”:339,“function”:“getItemsFromRequest”,“class”:“OCA\Circles\Db\ShareWrapperRequestBuilder”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/Service/ShareWrapperService.php",“line”:180,“function”:“getSharedWith”,“class”:“OCA\Circles\Db\ShareWrapperRequest”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/circles/lib/ShareByCircleProvider.php",“line”:557,“function”:“getSharedWith”,“class”:“OCA\Circles\Service\ShareWrapperService”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Share20/Manager.php",“line”:1375,“function”:“getSharedWith”,“class”:“OCA\Circles\ShareByCircleProvider”,“type”:"->"},{“file”:"/var/www/nextcloud/apps/files_sharing/lib/MountProvider.php",“line”:90,“function”:“getSharedWith”,“class”:“OC\Share20\Manager”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Config/MountProviderCollection.php",“line”:118,“function”:“getMountsForUser”,“class”:“OCA\Files_Sharing\MountProvider”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:429,“function”:“addMountForUser”,“class”:“OC\Files\Config\MountProviderCollection”,“type”:"->"},{“file”:"/var/www/nextcloud/lib/private/Files/Filesystem.php",“line”:354,“function”:“initMountPoints”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/private/legacy/OC_Util.php",“line”:326,“function”:“init”,“class”:“OC\Files\Filesystem”,“type”:"::"},{“file”:"/var/www/nextcloud/lib/base.php",“line”:1029,“function”:“setupFS”,“class”:“OC_Util”,“type”:"::"},{“file”:"/var/www/nextcloud/index.php",“line”:36,“function”:“handleRequest”,“class”:“OC”,“type”:"::"}],“File”:"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php",“Line”:92}},“CustomMessage”:"–"}}

and here from nextcloud apache log file:

xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/viewer/js/viewer-main.js?v=d099ea77-0 HTTP/1.1” 200 339197 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/recommendations/l10n/it.js?v=d099ea77-0 HTTP/1.1” 200 951 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/weather_status/js/weather-status.js?v=d099ea77-0 HTTP/1.1” 200 416029 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/activity/js/activity-dashboard.js?v=d099ea77-0 HTTP/1.1” 200 281333 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/user_status/l10n/it.js?v=d099ea77-0 HTTP/1.1” 200 1325 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/recommendations/js/dashboard.js?v=d099ea77-0 HTTP/1.1” 200 181104 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:27 +0100] “GET /apps/user_status/js/dashboard.js?v=d099ea77-0 HTTP/1.1” 200 346288 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/firstrunwizard/js/activate.js?v=d099ea77-0 HTTP/1.1” 200 808 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/firstrunwizard/l10n/it.js?v=d099ea77-0 HTTP/1.1” 200 4894 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/firstrunwizard/js/about.js?v=d099ea77-0 HTTP/1.1” 200 940 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/notifications/l10n/it.js?v=d099ea77-0 HTTP/1.1” 200 1988 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/dashboard/l10n/it.js?v=d099ea77-0 HTTP/1.1” 200 1376 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/dashboard/js/dashboard.js?v=d099ea77-0 HTTP/1.1” 200 158401 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/user_status/js/user-status-menu.js?v=d099ea77-0 HTTP/1.1” 200 256688 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /apps/notifications/js/notifications-main.js?v=d099ea77-0 HTTP/1.1” 200 329151 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:28 +0100] “GET /core/js/dist/unified-search.js?v=d099ea77-0 HTTP/1.1” 200 154477 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /index.php/apps/recommendations/api/recommendations/always HTTP/1.1” 412 854 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /index.php/apps/dashboard/undefined/img/notifications.svg HTTP/1.1” 500 5330 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /index.php/apps/dashboard/undefined/img/notifications-new.svg HTTP/1.1” 500 5330 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /ocs/v2.php/apps/notifications/api/v2/notifications HTTP/1.1” 200 1554 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /apps/firstrunwizard/img/apps/tasks.svg HTTP/1.1” 200 1282 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /index.php/apps/dashboard/undefined/js/firstrunwizard-main.js HTTP/1.1” 500 5330 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /ocs/v2.php/search/providers?from=%2Fapps%2Fdashboard%2F HTTP/1.1” 200 1100 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /apps/firstrunwizard/img/apps/social.svg HTTP/1.1” 200 925 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /apps/firstrunwizard/img/apps/deck.svg HTTP/1.1” 200 1208 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /apps/firstrunwizard/img/apps/groupfolders.svg HTTP/1.1” 200 2325 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /apps/firstrunwizard/img/apps/notes.svg HTTP/1.1” 200 5694 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:15:51:29 +0100] “GET /cron.php HTTP/1.1” 200 956 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:16:06:30 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5687 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:16:21:30 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5687 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:16:36:29 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5686 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:16:51:30 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5688 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:17:07:08 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5687 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”
xxx.xxx.xxx.xxx - - [02/Feb/2022:17:21:29 +0100] “GET /index.php/csrftoken HTTP/1.1” 200 5687 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36 Edg/97.0.1072.76”

Is that enough?

Looks like you have a database issue.
Can you check into that?

Maybe this helps (haven’t checked in detail now):
https://bobcares.com/blog/mysql-error-1038/

Exactly; I was noticing the same thing.
in another blog I read that the problem could be Mysql:

Nextcloud 21 will no longer support this version and requires MySQL 8.0 or MariaDB 10.2 or higher.

I did not use MariaDB. Is that the problem?

in stackexchange I read that it is not recommended to increase the sort_buffer_size of Mysql.
What do you think?

As I understood your first message, you didn’t perform a Nextcloud update and this issue just came out of nowhere, right? (Apart from the certbot installation, which seems unrelated)

If that’s the case and there was no Nextcloud update and not a specific update to the DB, I’d say this has nothing to do with unsupported DB versions.

I would try the config value first. And maybe restart the whole machine once.

I understand.
I would like to contact my client first because there are other Mysql databases in use and I would not want to cause problems, being a server in production.