Error trying to create admin user: failed to connect to the database .an exception occured in driver :SQLSTATE:2002 no such file or directory .
data/owncloud.log
{"reqId":"WkHbOvvibJoDjWD49MfdSQAAAAQ","remoteAddr":"202.63.215.48","app":"PHP","message":"Class 'PDO' not found at \/mnt\/test\/owncloud\/lib\/private\/setup.php#113","level":3,"time":"2017-12-26T05:16:42+00:00","method":"GET","url":"\/index.php","user":"--"}
[Tue Dec 26 06:08:41.043627 2017] [:error] [pid 53725] [client 202.63.215.48:27680] PHP Fatal error: Class 'PDO' not found in /var/www/html/owncloud/lib/private/setup.php on line 113
If i'm getting a "PHP Fatal error" the first thing i would do is to search some online resources like a search engine or the PHP manual to find a solution. I think it could be also possible that you just have not fulfilled all requirements for ownCloud, then the manual of ownCloud about the prerequisites might help as well.
I think another machine can have another installed packages or a complete different base install. If both machines would share the same base then i think you wouldn't see this message.