Creating Copy of Contao-Based Website

Contao 4.x was built with Symfony Framework and due to using some additional code caching duplicating a site takes a little more than it did with previous versions.

Copy Data

First you need to copy all files of existing website into new folder. This is as simple as it sounds.

cp -pR my-website copy-of-website

Next the database must be copied, too.

mysqldump -u oldDbUser -p oldDbName >my-dump.sql
mysql -u newDbUser -p newDbName <my-dump.sql

This, of course, requires having set up a new database with its separate user and a different password.

Adjust the file copy-of-website/app/config/parameters.yml and set the new database configuration. In addition you need to change the value of secret to a different value.

Refresh Cache

Here comes the extra step required due to code caching. Log in to the server via SSH or open a console by any other means. Make sure you are the user as is used by webserver or PHP engine for accessing files later. Then run these commands:

cd copy-of-website
vendor/bin/contao-console cache:clear
vendor/bin/contao-console cache:warmup

This will remove the code cache of original website and replace it with a new version. Without this the new website keeps modifying the database of original one due to not actually checking parameters.yml file on every request but using some derived code from cache.

Troubleshooting

If you get blank screens or any errors after refreshing cache you most probably missed to run those commands as user of webserver or PHP engine. You might need to fix the ownership with a command similar to this one:

cd copy-of-website
chown www-data:www-data -R var/cache/prod