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New Member

PIX 501>>> Linksys Problem

Hi All,

I have a PIX 501 firewall, which is connected to a Linksys WAG54G (as my ADSL modem)

I have been using the PIX before I moved location, and I want to keep it exactly the same, just with a new public IP Address. I have changed the configuration and I can't get the PIX to connect to the Linksys!!!

They are both in the same IP range, and if I plug my laptop into the Linksys, I can get out to the Internet. However, I cant ping the Linksys when I am telnetted into the PIX. Also, if I plug my laptop straight into the PIX, I cant ping that either

It seems my PIX is the problem, but I can't see where!

I have another PIX with the same Linksys on a different Internet connection, and this one works fine

Any ideas?


Re: PIX 501>>> Linksys Problem

post the config please

New Member

Re: PIX 501>>> Linksys Problem

Config attached. Any help is appreciated!

Re: PIX 501>>> Linksys Problem


After seeing your config your outside port is marked as auto for both speed and duplex.

to isolate and to negate the probabilities involved in this problem would suggest to hardcode the speed and duplex as well in the first line to check up the communication after that.


New Member

Re: PIX 501>>> Linksys Problem

Hi there. I have changed it to 100/Full, and still no joy?


New Member

Re: PIX 501>>> Linksys Problem

Make sure that you DO NOT have the software firewall up on the Linksys. Not sure what your configuration is but mine was this:

Firewall to Linksys Router to ISP

Seems sequence number issues come up when you have firewalls back to back. Hope this helps.

New Member

Re: PIX 501>>> Linksys Problem


thanks for that suggestion. I have checked, but the firewall is definately off. Is there anything else I can check?


Re: PIX 501>>> Linksys Problem

I guess this is because you have configured a public IP on the outside PIX interface. Do you really have a public IP range in the inside LAN on the Linksys router ?


Linksys outside 217.40.y.x

Linksys inside (Private IP)

PIX outside (Private IP)

PIX inside 172.16.x.y (Another Private IP)

PIX default gateway is the Linksys IP =

Then for all the NAT setup you will need to NAT (Port forward) all the setting from the Linksys router to the PIX.



New Member

Re: PIX 501>>> Linksys Problem

Do you need to configure the linksys router as a transparent bridge.

If this is turned on the linksys will only handle dsl signalling.

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