Issue with DNS server forwarder IPv6 and regexp

Athan · March 8, 2018, 12:14pm

I need to block some specific domain at Mikrotik’s DNS level.
Statically configured domain (name=example.com) works with IPv6 enabled network but using regex instead it doesn’t (regexp=“example.com”)

I don’t know if it’s a bug but seems that regexp only works with domains not having AAAA record, or something like that.

Any help is appreciated!

Sob · March 8, 2018, 2:48pm

This works here (tested with latest bugfix/current/rc):

/ip dns static
add address=2001:db8::1 regexp="forum\\.mikrotik\\.com\$"

Athan · March 8, 2018, 8:34pm

Yes it works, though the following doesn’t and I wonder why. A loopback is a loopback after all…

/ip dns static
add address=127.0.0.1 regexp="forum\\.mikrotik\\.com\$"

I’m afraid I have to write all static dns entries twice, one using IPv4 loopback address and a second with IPv6.

Sob · March 8, 2018, 11:44pm

Sure, 127.0.0.1 is IPv4 address and you create only A record, when you use it. If you want AAAA, you need to use IPv6 address, so ::1.

Athan · March 9, 2018, 1:09am

I hoped that MT’s forwarder used common entries for both IP protocols similarly to dnsmasq “address”.
Anyway, thanks for helping me Sob