Issue with NextDNS endpoint 45.90.28.32 returning unreachable Akamai IPs

Possible issue with NextDNS Akamai routing / resolver selection causing unreachable websites

I am using NextDNS via DNS-over-TLS on an ASUS router running Merlin firmware.

Configuration:

• NextDNS profile configured with DoT

• Router DoT servers:

  • 45.90.28.32

  • 45.90.30.32

I noticed that some websites intermittently become unreachable (for example tweakers.net, hotels.com, and bol.com). The DNS resolution succeeds, but the returned Akamai IP addresses sometimes cannot be reached on TCP port 443.

Example:

Using NextDNS 45.90.28.32:

tweakers.net → 95.101.239.157, 95.101.239.133

These IPs time out.

Using NextDNS 45.90.30.32:

tweakers.net → 2.16.6.218, 2.16.6.219

These work correctly.

Using Cloudflare DNS (1.1.1.1) also returns working Akamai IPs.

test.nextdns.io showed different NextDNS resolver locations:

Problematic path:

destIP: 45.90.28.32
server: zepto-ams-1

Working path:

destIP: 45.90.30.32
server: vultr-ams-1

As a test, I removed 45.90.28.32 and kept only 45.90.30.32.

I also tested device-specific NextDNS configurations:

• Chrome Secure DNS:

  https://dns.nextdns.io/<profile>/<device>

• Android Private DNS:

  <device>-<profile>.dns.nextdns.io

When using these device-specific configurations, the issue returned. test.nextdns.io showed that Chrome was using:

protocol: DOH
server: zepto-ams-1
destIP: 45.11.106.155

After removing the device-specific settings and using only the router DoT configuration, the websites started working again.

It appears that certain NextDNS resolver/edge paths may return an incorrect Akamai edge selection, possibly related to ECS or resolver location.

Could this be investigated?

(first I thought it was only my device id that caused the problem, I tried removing that bug post which was here: https://help.nextdns.io/t/x2yjhn0)