ldap_unbind kills the link descriptor. So, if you want to rebind as another user, just bind again; don't unbind. Otherwise, you'll have to open up a new connection.
(PHP 4, PHP 5, PHP 7)
ldap_unbind — Unbind from LDAP directory
$link_identifier
)Unbinds from the LDAP directory.
Returns TRUE on success or FALSE on failure.
ldap_unbind kills the link descriptor. So, if you want to rebind as another user, just bind again; don't unbind. Otherwise, you'll have to open up a new connection.