Zyxel Prestige 643 ADSL Router - Cannot connect to access the menu settings

Clare United

Hi,
does anyone know how to connect to the Prestige 643 ADSL Router where the IP address is unknown. An IP address was entered at some stage but it is unknown what ip range was used so I cannot connect through the browser or Hyperterminal using an IP address. (I've tried a number of the standard default ones like 192.168.1.1 /.254 etc)

I tried connecting through the console with hyperTerminal to com1 but nothing appears on screen except a flashing cursor.
I'm not sure whether the cable is wired correctly.(pins 2 & 3 crossed to 3 & 2 and 5 to 5 connected) Is this the correct wiring for console connection.

There is no reset button on the Prestige 643 so is there a way of resetting that model to its factory defaults

Basically I need to know 2 things -

(1) Is there any way to reset the Prestige 643 to its factory default settings (IP address & passwords) - There is no reset button.

(2) If (1) above cannot be done, do you know the procedure for connecting through the console port (cable wiring etc.) to make the necessary IP address change so that I can connect through the browser again.

Thanks

Thomas_S_Hunterson

Don't use com1, use the TCP/IP option in Hyperterminal.

Go into DOS and runthe following command:

tracert www.google.ie

The first numered line that appears on screen will have your router's IP address on it and you should be able to connect through that.

Just connect it as you normally would to access the internet and use Hyperterminal to telnet the router.

Clare United

Thanks for the info but how do you use tracert without knowing what the router IP address is? I tried it on both www.google.ie and googles ip address but I just get a "can't resolve host" or a unreachable host" error


As the routers address is unknown, I don't know what address range was used on it. It could be any of the non routable Ip address ranges assigned for private address use.

My PC is setup for the 192.168.1.x range where as the 643 router could have one of the 192.168.10.x ranges ( I just don't know). That is why I need to know if there is a factory reset which I assume would default the address back to 192.168.1.1 or if I can get in through the console port and manually change it back to 192.168.1.1

Thomas_S_Hunterson

You could try downloading a port scanner or anetwork scanner that would look for active devices on network and give you their IPs along with their open ports. You usually specify a range of IP addresses and the software will go through them one by one

Have a google for IP Tools

BoB_BoT

you could give this a try.
have the router turned off, connect the com port on the router using the DB9 cable (serial cable).

Launch hyperterminal (or equivalent) and create a new connection.
Give it any name, set the port to com1, on the next screen select bits per second 9600, set the data bits to 8, parity none, stop bits 1 and the flow control to None.

Now turn on the router and you should see it starting to boot. If this doesn't work, try com2 instead.
Once it's finished booting you should either be asked for a user name/password or you'll be in the system menu. Select the factory reset or configure it as you see fit.

-Rob

Clare United

Thanks for all the info.
Problem Solved (so no need to reset Router or make up cables whew!!!!!)

I used a Sniffer Program from NetworkActiv and it was able to pick up the router IP address even though it was in a different IP range to the PC trying to connect to it.

Once I got the IP address of the router, I changed my PC to match the same IP address range and was then able to connect using the web browser and make the nescessary changes in the Router.

Thanks Sean for pointing me in the right direction - very much appreciated.