Where are the config files for the DHCP client to the WAN?

[IsaacFL]

I just was wondering if there was a way to customize the DHCPv6 client side and if so where to see the config files to see what the router is doing on its own.?
I am teaching myself ipv6, and have a working ipv6 network, but was curious how configurable the router is when gets it's ipv6 prefix. ie could I specify a different prefix size etc.
Sometimes I learn the most just looking to see how the config file is set up.

 

[thelonelycoder]

Look at the /etc/dnsmasq.conf file, compare it with IPv6 disabled and enabled, the added entries are IPv6 related.
Notable are the -ra / ra- entries, the Routing Advertisments.
Always helpful is the Dnsmasq man page and the command dnsmasq --help in a terminal.

 

[thelonelycoder]

Since you asked and I did not specifically mention it: The resolv file for DNS servers is referenced in the dnsmasq.conf file.
resolv-file=/tmp/resolv.conf
servers-file=/tmp/resolv.dnsmasq

 

[IsaacFL]

I was asking about the WAN side. How does the router negotiate the IP with the ISP?

My IPv6 is working well, but was wondering what was under the hood on the ISP side. How is it decided what size prefix to give the router, etc.

I think of that (maybe incorrectly) as the DHCP client on the router that interfaces to the ISP and does it have any configuration files. I think of dnsmasq as the DHCP server.

 

[thelonelycoder]

I was asking about the WAN side. How does the router negotiate the IP with the ISP?

Your title asks for the config files. The ones mentioned are the user configurable ones. More settings are stored in NVRAM.
But I believe most of what you are interested in is in closed or nearly indecipherable Asus code. For IPv4 this would be Wanduck, I'm not sure IPv6 is handled by it as well.

 

[IsaacFL]

I thought that might be the case, since I couldn’t find anything in my poking around.

 

[john9527]

Look at /etc/dhcp6c.conf for the ipv6 negotiation with the isp.
The router advertisement is handled in /etc/dnsmasq.conf in the latest merlin (on my fork, it's /etc/radvd.conf)