or to use the service name for your db instance and let TNS to sort the connection details for you like this:
$dblink= oci_connect($my_user, $my_pwd, 'KZT');
I favour the second option because swapping servers or making any server changes only requires a change to your TNS entry and not all of you applications. You do need the oracle TNS set up on your server 1 to gain connection. The easiest way is to install and configure an Oracle client on server 1. I would guess your problem may be because of a lack of the TNS and required binaries on your server1. The php engine uses Oracle binaries which do not come as a part of the php install.