The frontend does a "ps" check (if( (exec('ps -ef|grep zabbix_server|grep -v grep|wc -l')>0) || (exec('ps -ax|grep zabbix_server|grep -v grep|wc -l')>0) )) to determine if the backend server is running.

This will cause a problem if the backend is not on the same machine.

Here is a quick fix I did, not sure if it's the best but it works for me:

$checkport = fsockopen($ZBX_SERVER, $ZBX_SERVER, $errnum, $errstr, 2);
if($checkport)

{ $status["zabbix_server"] = S_YES; }

else

{ $status["zabbix_server"] = S_NO; }

I had to also add a global for $ZBX_SERVER & $ZBX_SERVER_PORT to the function to get it working.