Linux: check system, PHP and MySQL date and time

Sometimes it can be useful to verify if system, PHP and MySQL date and time is synced.
I am using this set of commands to check:

# date ; php -r "echo date('r').PHP_EOL;" ; mysql -e "SELECT NOW();"

Also, it can be useful to check the same information on remote server without logging in to it. It can be done using the same above set of commands plus ssh utility:

ssh 'date ; php -r "echo date(\"r\").PHP_EOL;" ; mysql -e "SELECT NOW();"'