[Devops] [help] a1 biz internet

[spam at lamer.sk]

Hi everyone,

sorry for being offtopic, this seemed like a better place than the 
general metalab mailinglist.

tl;dr -> assistance with A1 biz gateway dhcp/bridge configuration needed.

Recently I came across a friend living in .at with an A1 internet 
connection. From what I've gathered, his subscription is a 'biz 
internet' one, with technicolor TG670 modem as a provided gateway with a 
static public v4 IP, NAT and DHCP.

Before, there was a 10.0.0.0/24 network, with gw on 10.0.0.138, dhcp 
server enabled, all good. Now we want to reconfigure the network.

To reconfigure the network and avoid conflicting subnets with his new 
installation, we wanted to change LAN range to something different, 
let's say 192.168.100.0/24, with .1 being the gw (tg670), masquerade on.

As there is no access (is there?) to config options for the user on the 
tg670, we had to call biz support line which turned out to be a mistake 
-> the dhcp has been reconfigured by them remotely, handing out IPs in 
the new range (192.168) but there is no gateway on 192.168.0.1 (no arp, 
no ping..).

However - configuring old IP on my laptop (10.0.0.x) and setting default 
gw statically, internet is rechable, which leads me to think the DHCP 
has been reconfigured, but the LAN interface of the gateway still has 
the old IP (10.0.0.138 - default). I tried screaming, yelling, crying, 
everything, I couldn't get a hold of anyone who could fix this for me, 
so to at least keep the installation in this broken state online, I had 
to do some crazy routerboard config.

So, two questions:
1) can someone help me with sorting this A1 biz? how? :)
2) is it possible to put this into bridge/dmz mode to map the public IP 
to one host 'behind' the gateway and do everything there (nat,dhcp,dns)?

Thanks a lot!

bon