RealVNC firewall troubles on 3Com officeconnect router

Windows IP-konfigurasjon


Ethernet-kort Lokal tilkobling:

Tilkoblingsspesifikt DNS-suffiks : lan
IP-adresse . . . . . . . . . . . : 10.0.0.2
Nettverksmaske . . . . . . . . . : 255.255.255.0
Standard gateway . . . . . . . . : 10.0.0.138

Ethernet-kort Trdls nettverkstilkobling 2:

Tilkoblingsspesifikt DNS-suffiks :
IP-adresse . . . . . . . . . . . : 192.168.10.254
Nettverksmaske . . . . . . . . . : 255.255.255.0
Standard gateway . . . . . . . . :

C:\Documents and Settings\Eier>ipconfig /all

Windows IP-konfigurasjon

Vertsnavn . . . . . . . . . . . :
Primr DNS-suffiks . . . . . . . :
Nodetype . . . . . . . . . . . . : Hybrid
IP-ruting aktivert . . . . . . . : Nei
WINS Proxy aktivert. . . . . . . : Nei
Skeliste for DNS-suffiks. . . . : lan

Ethernet-kort Lokal tilkobling:

Tilkoblingsspesifikt DNS-suffiks : lan
Beskrivelse . . . . . . . . . . : National Semiconductor DP83815-basert
PCI Fast Ethernet-kort
Fysisk adresse . . . . . . . . . :
DHCP aktivert. . . . . . . . . . : Ja
Automatisk konfigurasjon aktivert: Ja
IP-adresse . . . . . . . . . . . : 10.0.0.2
Nettverksmaske . . . . . . . . . : 255.255.255.0
Standard gateway . . . . . . . . : 10.0.0.138
DHCP-server. . . . . . . . . . . : 10.0.0.138
DNS-servere. . . . . . . . . . . : 10.0.0.138
Leasingavtale mottatt. . . . . . : 31. januar 2008 21:30:33
Leasingavtale utgr. . . . . . . : 1. februar 2008 21:30:33

Ethernet-kort Trdls nettverkstilkobling 2:

Tilkoblingsspesifikt DNS-suffiks :
Beskrivelse . . . . . . . . . . : 3COM OfficeConnect Wireless 11g Compa
ct USB Adapter
Fysisk adresse . . . . . . . . . :
DHCP aktivert. . . . . . . . . . : Ja
Automatisk konfigurasjon aktivert: Ja
IP-adresse . . . . . . . . . . . : 192.168.10.254
Nettverksmaske . . . . . . . . . : 255.255.255.0
Standard gateway . . . . . . . . : 192.168.10.1
DHCP-server. . . . . . . . . . . : 192.168.10.1
DNS-servere. . . . . . . . . . . : 192.168.10.1
Leasingavtale mottatt. . . . . . : 31. januar 2008 21:30:58
Leasingavtale utgr. . . . . . . : 19. januar 2038 04:14:07

Routing table from the router:

Flags Network Address Netmask Gateway Interface Metric
C 127.0.0.1 255.255.255.255 127.0.0.1 Loopback 1
C 224.0.1.134 255.255.255.255 192.168.10.1 LAN 1
S 0.0.0.0 0.0.0.0 10.0.0.138 WAN 1
C 10.0.0.0 255.255.255.0 10.0.0.1 WAN 1
C 192.168.10.0 255.255.255.0 192.168.10.1 LAN 1

--------------------------------------------------------------------------------
Note: Flags : C - directly connected, S - static, R - RIP, I - ICMP Redirect.

I have some troubles to understand why the 10.x network is configured and part of the routing table...I can not find anything that specify a 10.x network in the router...

You've got BOTH the Nic(wired) and Wireless adaptors running and connected.
In addition, you have no DEFAULT Gateway.

It is possible to make this work, but I suspect this is not what you intended to do.

If you do intend to run this way, you need to add some ROUTES to your routing table
to tell your system where to read/write packets based upon the remote destinations.
Be advised: If you add routes to make the wireless repsond AND it is not connected,
then those data streams will just fail with Host Not Accessible

The reason both the Nic and Wireless are enabled is the fact that I'm unable to connect to the PC (from Internet using VNC, remote desktop, pcAynwhere etc) when only the wireless is enabled. Therefore, I enabled the Nic as well in order to connect to the PC.

Why is a 10.x IP allocted to the Nic, as a 192.x is allocated to the wireless? I would guess that both the Nic and wireless should be allocated a 192.x IP (two different IP's obviously) by the 3Com DHCP?

Oook.. This is a mess. Now, are you really fscking sure that you have only one router? Go to your 3com, grab a hold of every wire going into the box and identify the device at the other end. Then, unplug this 3com thing and see if all the your wireless and wired computers get disconnected.

It looks like the WAN side of the router is 10.0.0.x and the LAN side is 192.168.10.x. This is OK. But then the wired computer shouldn't be receiving the 10.0.0.x address unless you plugged it in the wrong device.

Thanks a lot for your help

You are correct - it seems to be two devices connected. Please see updated topology.

Sorry for the confusion - the network is installed at my parents house, 500km away....

Initially PC1 was connected accordint to "test 1". Now, we also have tried "test 2".

I would guess that the Thomson device only should alloce 10.x IP to itself and the 3Com router, not PC1?

Great news! It's working ...

The Thomson router/modem was configured to route VNC directly to one of the network interfaces of the PC. I changed the Thomson router to send these packets to the 3Com router instead. The port forwarding configured at the 3Com router then ensured that the traffic was received at the correct computer / interface. Now I'm able to connect to both computers using VNC, remote desktop and pcAnywhere (also when there is no wired connection).

Thanks a lot for all your valuable help. It's much appreciated

OK, good that you got it sorted out.

You may want to consider a different set up where the Thomson and 3com are connected via their LAN ports. There would be only one router involved, giving less management overhead and reducing network latency. We have several threads on these forums about connecting two routers.

Hi, I would like to check my 3com 3C888 router to see if needs the 2.2.0 upgrade. The upgrade Wizard provides a OCRDA address 192.168.200.254 that doesn't work. How can I check my router to see if it needs upgrading, it runs slow. MarkNC

the only issue is what do you have vs. what is available

log into the router config page using your browser
(run->cmd /k ipconfig /all will show you the GATEWAY address)

poke about to find the (firmware) version installed.

Then get another browser window, go to the OEM website and find there support/download page and see what is available for your make+model number.

If yours doesn't match that which is available, then you need it! download and install it

The Computer-A setup is inconsistent with the router, as you have TWO different
subnets 10.x wired and 192.x wireless to the same router. Whether wired or wireless,
a router will normally support ONE subnet, not two.

Secondly, you can not ping from one end of a VNC connection all the way thru to the other end,
as the port forwarding is on PORTS and ping is not a port but a Protocol and
will not follow the forwarding path.

As you have Server-A and Server-B in one location, get your VNC to connect from one to the other
as that will be faster to debug. Once that works, getting from the Remote Client to System-A will be better understood.