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Contributor III
May 4, 2004
Question

VNC

  • May 4, 2004
  • 2 replies
  • 9711 views
In a LAN protected by a FGT60 i have a pc (192.168.1.169) which run tightVNC (just like RealVNC) on port 5900. What i want to do is to connect to tightVNC on 192.168.1.169 from another pc external from my LAN and connected to the internet (of course). Here is the things i did: 1) under FIREWALL/service/custom i created my service in this way: 2) under FIREWALL/virtual IP i clicked on " new" (my external interface wan1 has IP 192.168.50.2/255.255.255.0 and wstation2 is pc running tightVNC server, IP of wstation2, as already said, is 192.168.1.169): Name --> vnc_su_wstation2 External interface --> wan1 Type --> static NAT (no port forwarding) External IP Address --> 192.168.50.33 (i set this class IP because i think it has to be on the same segment of wan1) Map To Ip --> 192.168.1.169 (wstation2 of course) 3) under FIRERWALL/policy and " from wan1 to internal" i set thi policy: Source --> wan1_all Destination --> vnc_su_wstation2 Schedule --> always Service --> vnc_Bezzi Action --> accept (of course) I have not flagged NAT because virtual IP already makes NAT, in this case from 192.168.50.33 to 192.168.1.169 No traffic shaping, no antivirus, no log Well, if i try to connect to my tightVNC server from an external pc opening thightVNC client (viewer) and inserting my public IP (80.17.*.* - i don' t want to say to you my IP ) i can' t connect and this message appear to me: " failed to connect" . Someone can tell me where i' m wrong?? Thanks in advice. PS: between FGT60 and internet there' s a cisco router, but mi isp said that by default all ports from EXT to INT are opened....

    2 replies

    Contributor III
    May 10, 2004
    I' d suggest you to sniff the your external/internal interfaces connect your FGT using SSH/serial to gain CLI access, then type diag sniff interf external filters ' port 5900' then check how incoming packets are forged (src IP:port, dst IP:port) but I guess your problem comes from the Cisco router, except if your ISP has set a DNAT rule saying WAN IP (dst) becomes 192.168.50.33 .. then FGT seeing 192.168.50.33 does another NAT saying 192.168.50.33 becomes 192.168.1.169 .. then the connection should be OK
    Contributor III
    May 10, 2004
    The problem wasn' t in my policy, but in a static NAT my provider had to do on one of my public IPs, a NAT from " my_public_IP" to " my_internal_private_IP" on EXT interface of FGT. Now all works fine
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