Having an issue with Raspberry Pi 4 router

[simijames3104]

Hello everyone,

I hope everyone's fine. I am new to this forum, actually I came to this forum while searching for my issue. That's the thread I am talking about: [url]https://archlinuxarm.org/forum/viewtopic.php?f=15&t=16910[/url] but there's no solution.

I am working on a Raspberry Pi 4, I am using this model: [url]https://www.theengineeringprojects.com/2021/03/what-is-raspberry-pi-4-pinout-specs-projects-datasheet.html[/url] and I am trying to make it work as a router.

I have connected it via Ethernet to my main internet provider and am now making it act as a DNS server. Now when I try to port forward the DNS request to my original internet provider, I receive error during prerouting. I get this error:

$this->bbcode_second_pass_code('', 'tables: No chain/target/match by that name.')

Although the first request works fine, the below one:
$this->bbcode_second_pass_code('', 'sudo iptables -A fw-open -p udp -d 10.24.90.247 --dport 53 -j ACCEPT')

Please help me out here.

Thanks.