The directory structure is different with SNAP installation than with manual installation:
Snap tooling offers some kind of commands, that can be used e.g. to restart apache server:
sudo snap restart nextcloud.apache
You can also renew certificate easily with the following command:
sudo nextcloud.enable-https lets-encrypt
In order to be able to execute this command, you should be logged in with the user, which the nextcloud installed with and execute the command with „sudo“. Otherwise the following error message is being shown:
Command ’nextcloud.enable-https‘ is available in ‚/snap/bin/nextcloud.enable-https‘ The command could not be located because ‚/snap/bin‘ is not included in the PATH environment variable. nextcloud.enable-https: command not found.
The path of certificates can be found in the following file: /snap/nextcloud/current/conf/ssl.conf