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1231 AP and DNS servers


I have a simple configuration. An ADSL modem and an access point that acts as a dhcp server for the wireless clients.

The problem is that the access point does not advertise the dns servers that are configured at the adsl modem to wireless clients and i have to insert them manually in order to connect to the Internet.

Any suggestions?


Re: 1231 AP and DNS servers

If the dns fixup protocol's max-length is set to the default 512 bytes, you are unable to resolve some domains. This issue may occur if a firewall blocks the transfer of UDP packets that are larger than 512 bytes.

With Extension Mechanisms for DNS (EDNS0), "Extension Mechanisms for DNS (EDNS0)," DNS requestors can advertise UDP packet size and transfer packets larger than 512 bytes. By default firewall have security features turned on that block UDP packets that are larger than 512 bytes. As a result, DNS queries may fail and other DNS traffic connections may fail.

Community Member

Re: 1231 AP and DNS servers

the last line did the trick

interface Dialer1

description $FW_OUTSIDE$

mtu 1492

ip address negotiated

ip access-group 103 in

ip inspect DEFAULT100 out

ip nat outside

ip virtual-reassembly

encapsulation ppp

dialer pool 1

no cdp enable

ppp authentication pap callin

ppp pap sent-username password 7 xxxxxxxxxx

ppp ipcp dns request accept

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