How to monitor remote host from cacti server

[skipsteps]

Hello Everyone!

I would like to monitoring Remote Host (QNAP NAS) from Cacti Server. Cacti Server is located in Head Office and Remote Host client will be located in Site Office. But I don't know which port numbers need to be opened in firewall (Fortinet 100D) at Head Office and another firewall (Netgear) which located in remote site office. Cacti Server (0.8.8b) has installed on Ubuntu Server 12.04 LTS. I would like to ask following questions.

1. Which port numbers need to be opened at both site of firewall? (I'd like to know whether TCP or UDP port details)
2. Which port numbers need to be opened at Cacti Server (Head Office) and Remote Host (QNAP NAS)?
3. Because of remote host is QNAP NAS (embedded linux), Do I need to use any other method??
4. Do I need to use SSH Tunnel (if i need to use SSH Tunnel, will be needed to install "socat" and need to be setup another ubuntu server at Site Office for working as ssh server? Its will be (Gateway) for Cacti Server and Remote Host.)

Help me please.
Thanks in advanced.

[cigamit]

If you are strictly using SNMP to monitor the remote server, you will need to allow UDP 161 through the firewall to the remote server.