It looks like there is an issue with
/var/run/gonit.sock. These are the permissions of a working instance:
jsalmeron@bitnami-magento-dm-2dd0:~$ ls /var/run/gonit.* -la
-rw-r--r-- 1 root root 4 Aug 29 08:42 /var/run/gonit.pid
srw-rw---- 1 root root 0 Aug 29 08:42 /var/run/gonit.sock
Moreover, I want you to do the following test as well. Could you enter your instance and execute these two commands?
curl -L localhost:80
curl -L localhost:81
If it only happens in the first one, then the problem is with Varnish. If it happens in both of them, then the issue is located in the PHP settings or the Magento configuration.
Hope it helps.
Javier J. Salmerón
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