I have the following situation:
I have a 4G LTE router that gets a dynamic IP from my ISP. In order to get a public IP i had to activate a free configuration option in my ISPs customer zone called "OpenInternet". Before that the public IP of my router was different to the 10.x.x.x address it got awarded from the ISP. Thus it was not making any sense to assign this private IP to a free dynamic host name from NoIP. Otherwise, after i had solved that problem my routers firmware knew how to automatically update its current IP address to NoIP provider of dynamic (managed) DNS. By that construction wanted to avoid the costs of leasing a static IP from my ISP and maybe also registering my own domain (in which case i also would not have known how to configure it properly).
Now i could access my server that is behind my router in a LAN 192.168.x.x even with ssh from outside by using port forwarding and port opening in the routers firewall. However, my apache2 still has problems and it always complains about non-resolved DNS and problems with DNS resolution, when using my dynamic DNS-name to test access from outside by let us say one Website speed test in the internet:
https://tools.pingdom.com/ . Since my router uses itself html-configuration it also blocks port 80 on the dynamic DNS and it made itself to be the host to which the dynamic DNS resolves. Thus i forwarded port 8080 to 80 on my apache2 server and this seemed to work, but the DNS resolution still did not work reportedly by the apache. Now i was concluding, that this is an issue with DNS resolution and now i am trying to setup a DNS name server couple on two of my local RaspBerrys. My internal devices that i care about use all static IPs so i could simply enter them into DNS configuration files, but what to do about the dynamically updated DNs? My router automatically updates its IP. Thus i don't need to update that. Do i still need to install a DHCP server alongside with the DNS server in order to deal properly with that dynamically managed DNS? What should i write in the reverse-DNS section in DHCP config? When determining my reverse DNS by let us say seraching for the current IP x.x.x.x of my router at
https://remote.12dt.com/lookup.php i get
x.x.x.x.wireless.dyn.drei.com
but actually the IP is assignet to xxx.freedynamicdns.net by a No-IP account, which is updated by the routers firmware.
/etc/bind/named.conf.local:
// Add local zone definitions here.
zone "network.athome" {
type master;
file "/etc/bind/db.network";
allow-update { key "rndc-key"; };
notify yes;
};
zone "0.168.192.in-addr.arpa" {
type master;
file "/etc/bind/db.192.168.0";
allow-update { key "rndc-key"; };
notify yes;
};
include "/etc/bind/rndc.key";
and /etc/dhcp3/dhcpd.conf:
# Basic stuff to name the server and switch on updating
server-identifier server;
ddns-updates on;
ddns-update-style interim;
ddns-domainname "network.athome.";
ddns-rev-domainname "in-addr.arpa.";
ignore client-updates;
# This is the key so that DHCP can authenticate it's self to BIND9
include "/etc/bind/rndc.key";