Strainge DHCP behavior on Wan port

[Styno]

So anyone in the Netherlands hooking his or her asus up to a Zyxel with a demon adsl connection, you have been warned!

Hmm, I have Demon Internet AND a Zyxel modem, but I haven't got problem with it at all....

[wiz]

Hmm, I have Demon Internet AND a Zyxel modem, but I haven't got problem with it at all....

Maybe you are lucky and I had bad luck to be on a subnet with a faulty dhcp config or something, or you don't use firewalling?

[Styno]

Maybe you are lucky and I had bad luck to be on a subnet with a faulty dhcp config or something, or you don't use firewalling?

Yes, I use the firewall. Weird.

[wiz]

well, if I look at the names of the systems I get the feeling it is a configuration error on the ISP site.

82.161.88.1 = bbned-vrf-04.router.nl.demon.net (also my default gateway)
82.161.247.54= bbned-pppoa-1.router.nl.demon.net.

So the original reply to the inital lease request ought to come from 82.161.247.54. My asus said it got is lease from my default gateway instead of the pppoa-1 router it is supposed to get it from.

[Styno]

I've just read the router HOWTO for the zyxel modem because I want to setup NAT as an extra security for my parents - otherwise they must rely on Windows security - and I discovered that DEMON requires a port to be forwarded.

IP Address Assingment moet meestal op automatisch staan. De meeste ISP's geven altijd hetzelfde vaste IP-adres. Zorg er bij een Prestige 652 voor dat in de WAN-WAN regels UDP-poort 68 (Bootp/DHCP) naar binnen wordt doorgelaten.

This rule is allready in the router when you received it so maybe you got a router where they forgot to setup this rule or you accidently deleted the rule.

[Oleg]

Styno, wiz has different setup as seems. His zyxel works in bridged mode as seems, while you're running zyxel as router. So, actually your zyxel is managing ISP dhcp stuff, not wl500g.

[wiz]

Yeps, my zyxel is running in bridged mode.

[Styno]

Styno, wiz has different setup as seems. His zyxel works in bridged mode as seems, while you're running zyxel as router. So, actually your zyxel is managing ISP dhcp stuff, not wl500g.

Ok, you're right about that, but it confirms that the iptables rule wiz found out a few topics above is right. Demon requires that for proper functionality somehow. Weird anyway, I don't have that rule in my Asus router (Zyxel is in bridge mode)....

[wiz]

just proves my point that it is in fact a configuration error on the subnet where I am at.

Luckily the helpdesk isn't ignorant at all so they didn't even wanted to ask network maintenance to check if this is a configuration error.

It is non standard not supported hardware, and it is solved now according to HD.

oh well me and helpdesks

[max]

Hi,
I have a similar problem. Zyxel modem Bridged, Demon Internet, Asus Wl 500G and USR 8054 AP. Since Mid december my Internet was having strange behaviour. I thought it was my USR8054. So i bought a new AP the asus. It did not work straight away so put the USR back on. Now i noticed that when I swap the AP, internet works again. So Almost every day I need to swap the access points in order to have internet access.
I will contact the helpdesk of Demon to report of this strange behaviour, this week.
The funny thing is that I still seem to have a demon internet IP number when it happens. I looked at the log and it looks like the DHCP lease expires.
Note that I already have demon internet for more then 1.5 years.

[Styno]

Maybe you can check on the network status page if the router of you neighbourhood central modem configuration has changed since you have the problems...

http://www.demon.nl/cgi-bin/dslstatus/dslstatus.pl

[max]

You were right Styno thx.

If have found this email..

"
Dear customer,

On 15-12-2004 comprehensive maintenance will be performed on central
equipment in the DSL network of our DSL partner bbned.

The maintenance is planned between 00:01 CET and 06:00 CET. As a
result of this work you will lose connectivity one or more periods of
time between said times. During the maintenance period it is necessary
that you leave your DSL modem turned on. We kindly request you not to
contact the Support department with inquiries concerning this work.
Our Support Agents have no additional information.

Your connection will be automatically restored afterwards. If this is
not the case we request you contact the Support department as soon as
possible on our (toll free) number 0800 - 336 66 68. To reach the
support department from a mobile phone, dial 0900-0212 (EUR 0.10 per
minute plus the usage costs of your mobile phone).

This work is essential for the continuity of the service.
"

[wiz]

Max,

Maybe you have more luck with the helpdesk, as yours did work correctly and all over sudden it is not working anymore despite the fact you haven't changed your network config.

I did install my asus after this maintenance job from demon. As I bought it around december 20th.

is your default gateway 82.161.88.1 = bbned-vrf-04.router.nl.demon.net by any chance?

[max]

Wiz,

No, would be a coincidence ;-)
My default gateway is.. 212.238.156.1.

Max