Redis errno=32 after Update to 23.0.3

[toneldaclan]

Nextcloud version : 23.0.3.2
Operating system and version : Ubuntu 20.04
Apache or nginx version : Nginx 1.21.6
PHP version : 8.0

The issue you are facing:
Redis shows errors errmo=32 Broken pipe after updating Nextcloud 23.0.2 to 23.0.3.
I used this guide to install my instance Nextcloud Installationsanleitung - Carsten Rieger IT-Services

Is this the first time you’ve seen this error? : Y

Steps to replicate it:

1. Upgrade to 23.0.3
2. I was unable to replicate this as this would need me to roll back and I don’t know how yet.

The output of your Nextcloud log in Admin > Logging:

[PHP] Error: Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe at /var/www/nextcloud/lib/private/RedisFactory.php#142

GET /apps/logreader/poll?lastReqId=yZM6JfyIKRc5iq6QTggU
from 192.168.0.51 by td1622 at 2022-03-29T15:55:21+08:00

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

{"reqId":"huZhuaFnhIyIIPD5RL1A","level":3,"time":"2022-03-29T15:58:50+08:00","remoteAddr":"192.168.0.41","user":"user74","app":"PHP","method":"GET","url":"/ocs/v2.php/apps/notifications/api/v2/notifications?format=json","message":"Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe at /var/www/nextcloud/lib/private/RedisFactory.php#142","userAgent":"Mozilla/5.0 (Windows) mirall/3.4.3stable-Win64 (build 20220225) (Nextcloud, windows-10.0.19044 ClientArchitecture: x86_64 OsArchitecture: x86_64)","version":"23.0.3.2"}
{"reqId":"St54ITSSCN6XGUEw7POb","level":3,"time":"2022-03-29T15:59:31+08:00","remoteAddr":"192.168.0.51","user":"user22","app":"PHP","method":"GET","url":"/apps/logreader/poll?lastReqId=huZhuaFnhIyIIPD5RL1A","message":"Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe at /var/www/nextcloud/lib/private/RedisFactory.php#142","userAgent":"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.84 Safari/537.36","version":"23.0.3.2"}
{"reqId":"QgSWDAaHploQmt9bcm13","level":3,"time":"2022-03-29T16:01:59+08:00","remoteAddr":"192.168.0.61","user":"user59","app":"PHP","method":"GET","url":"/csrftoken","message":"Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe at /var/www/nextcloud/lib/private/RedisFactory.php#142","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.74 Safari/537.36 Edg/99.0.1150.55","version":"23.0.3.2"}

The output of your Apache/nginx/system log in /var/log/____:

2022/03/29 15:58:50 [error] 206967#206967: *968 FastCGI sent in stderr: "PHP message: PHP Notice:  Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe in /var/www/nextcloud/lib/private/RedisFactory.php on line 142" while reading response header from upstream, client: 192.168.0.41, server: cloud.deltaearthmoving.com, request: "GET /ocs/v2.php/apps/notifications/api/v2/notifications?format=json HTTP/1.1", upstream: "fastcgi://unix:/run/php/php8.0-fpm.sock:", host: "redacted"
2022/03/29 15:59:31 [error] 206967#206967: *4 FastCGI sent in stderr: "PHP message: PHP Notice:  Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe in /var/www/nextcloud/lib/private/RedisFactory.php on line 142" while reading response header from upstream, client: 192.168.0.51, server: cloud.deltaearthmoving.com, request: "GET /apps/logreader/poll?lastReqId=huZhuaFnhIyIIPD5RL1A HTTP/2.0", upstream: "fastcgi://unix:/run/php/php8.0-fpm.sock:", host: "redacted"
2022/03/29 16:01:59 [error] 206967#206967: *549 FastCGI sent in stderr: "PHP message: PHP Notice:  Redis::select(): Send of 23 bytes failed with errno=32 Broken pipe in /var/www/nextcloud/lib/private/RedisFactory.php on line 142" while reading response header from upstream, client: 192.168.0.61, server: cloud.deltaearthmoving.com, request: "GET /csrftoken HTTP/2.0", upstream: "fastcgi://unix:/run/php/php8.0-fpm.sock:", host: "redacted"

[toneldaclan]

This is related to this issue

[Bug]: PHP ERROR (Redis::pconnect()) | redis server flooded with requests and connections

[toneldaclan]

The issue is due to low maxclients value of redis.
To fix this issue, change the maxclients value in /etc/redis/redis.conf.

maxclients = 10000