I am setting up an email server, nextcloud files server and DNS server on a machine running Ubuntu 20.04. I've used iRedmail for email and it seems to be working correctly. I need to setup the DNS service so that machines on the same network can access correctly the server.
For the DNS configuration I am using BIND9. Below is my named.conf.options
options { directory "/var/cache/bind";
listen-on-v6 { any; };
version "not currently available";
recursion yes;
querylog yes;
max-cache-size 30%;
forwarders {
8.8.8.8;
8.8.4.4;
};
dnssec-validation no;
auth-nxdomain no; # conform to RFC1035
allow-recursion { any; };
allow-query { any; };
};
It works correctly when used on the local machine. But does not work when I try to access it from another machine on the network. I have tried disabling the ufw firewall so I don't think the firewall is blocking the DNS requests.
Using
sudo tcpdump -u port 53
I can see lots of DNS requests coming through including when I request them manually from another machine on the network.
My netstat:
muruadmin@mail:~$ sudo netstat -lnptu | grep namedtcp 0 0 192.168.1.5:53 0.0.0.0:* LISTEN 63834/named
tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 63834/named
tcp 0 0 127.0.0.1:953 0.0.0.0:* LISTEN 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 192.168.1.5:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
udp 0 0 127.0.0.1:53 0.0.0.0:* 63834/named
So it appears to be listening over port 53.
I've also tried PortQry and have gotten this output:
portqry -n 192.168.1.5 -e 53 -p TCP
Querying target system called:
192.168.1.5
Attempting to resolve IP address to a name...
Failed to resolve IP address to name
querying...
TCP port 53 (domain service): FILTERED
Code:
portqry -n 192.168.1.5 -e 53 -p UDP
Querying target system called:
192.168.1.5
Attempting to resolve IP address to a name...
Failed to resolve IP address to name
querying...
UDP port 53 (domain service): LISTENING or FILTERED
Sending DNS query to UDP port 53...
DNS query timed out
I just don't know why it does not appear to be working. I'm sorry I've tried researching on this and seen this same problem a lot but none of their solutions seems to work for my case.
Thanks
