Any Network gurus here?
My network currently only able to connect to any site that support Ipv6, all ipv4 connection is dead.
Pinging 1.1.1.1 or any IPV4 will not get any responds.
LAN Ipv4 is working.
Ipv6 settings is current set as Native, not sure of the CGNAT implemented by TM breaks some settings or what.

you private ip that why IPV4 Will not get any responds

mine public ip so works fine IPV4 always responds

No.. that's not how that works.. if CGNAT straight up denies IPv4 ping requests, TM's own website wouldn't even work cause it still runs on IPv4.

If I had to guess for TS's case, it's probably TM's IPv6 breaking IPv4 dual stack connectivity, TM's implementation of IPv6, at least in my case is kinda weird, sometimes my internet connection just dies out of nowhere seemingly, and usually disabling IPv6 and re-enabling it solves it. For your case, check whether your PPPoE connection is getting an IP from TM. If you're using TM's default router, you can usually check in the main page (For my case I was using TP-Link and it shows my direct IP before.), if your IP is TM's public IP (As idk where you're from, TM's IP assignment pool has 1919 prefixes, you just have to search up your IP to see if it's a private IP or public IP. If it's 100.xx, then it's private IP) is lets say 175.141.x.x, then you get the idea. If it's obtaining a IPv4 address from TM, public or private, then you should have IPv4 connectivity.

Another possibility of what happening is your DNS servers are messed up, TM's PPPoE DNS server by default is 202.188.18.188 and 1.9.1.9. IF it's not showing you this two, try adding custom DNS and add those two, or you can try Cloudflare's 1.1.1.1 and 1.0.0.1. IF it's still not working, try disabling IPv6 entirely and reboot your router to see if your IPv4 connectivity restores after the reboot.

This post has been edited by yenchenje: Mar 17 2023, 05:46 PM

I been using custom DNS all this while - 1.1.1.1
I can see my public IP stated in the Asus Router: 100.79.XX.XXX

But if I use what is my IP on google, it can only detect my Ipv6 and not Ipv4.

Regards

If you run this https://test-ipv6.com does it show you both your ipv4 and ipv6 or any errors?

If you have both IPs google will usually show your IPV6 over IPV4

it only show IpV6 and not available for IPv4

When did it the issue start? Have you tried rebooting your router?

Let's not go in to "Reboot" Router :-).
It's all long pass that, since yesterday have been rebooted more than 30 times for troubleshooting.

No changes on Router, running on Asus Merlin 386.9

That's good, I'm also using Merlin 386.9.

Have you tried using the "Network Tools - Network Analysis" to ping with IPv4 and IPv6 ?

Did you change any custom DNS for IPv6, WAN or LAN settings?

If you try disable IPv6 will your IPv4 work?

Also since you're on merlin you can just disable wan and enable it back after 3 seconds it should request new IP for IPv4/IPv6 on the spot.

Ages ago, I used 1.1.1.1 before on Digi cellular network. It was blocked.

So... maybe you are having trouble resolving hostnames into IPv4.
1.1.1.1 is only an alias for a group of servers; maybe those group of servers are having problem resolving into IPv4.

.....

almost unlikely for a diverse and geographically- and administratively-separated DNS servers all to be having exact issue to return IPv4... either the whole CloudFlare DNS are misconfigured, a network-wide block is in effect, or you alone had misconfigured something that denied IPv4 from crossing your router.

You mentioned that even pinging don't work. I assume you are pinging IPv4 address and not hostname, right? Then probably you have misconfiguration on your side. If at least can ping outside IPv4, then there's chance to blame DNS resolution....

Nope, disable Ipv6 nothing will work.

Not really DNS issue as I am able to resolved the IP, but just nothing response from IPv4.

So something like this is happening on your network?


IPv6 ping works but any websites that still runs on IPv4 doesn't ping right?

This post has been edited by yenchenje: Mar 17 2023, 10:42 PM

C:\Users\zynge>tracert thestar.com.my

Tracing route to thestar.com.my [18.139.211.27]
over a maximum of 30 hops:

1 2 ms 2 ms 2 ms RT-AC88U-AAB0 [192.168.50.1]
2 102 ms 119 ms 60 ms 100.79.XXX.XXX
3 54 ms 109 ms 162 ms 10.233.65.54
4 * * * Request timed out.
5 * * * Request timed out.
6 * * * Request timed out.
7 * * * Request timed out.
8 * * * Request timed out.
9 * * * Request timed out.
10 * * * Request timed out.
11 * * * Request timed out.
12 * * * Request timed out.

It will hops 30 times and time out.

but for ipv6 site, no problem.

Yes basically that's what you describe.

So I can open www.google.com (ipv6) / www.youtube.com (ipv6).
But www.lazada.com.my will failed (ipv4) / thestar.com.my will failed (ipv4).

i don't use TM's default router

i using my own router i already check WAN IP its Public IP confirmed
i set google dns works fine my wan ip is WAN IP: 42.189.xxx.xxx

i use ASUS RT-AC68U no problem

i don't enable ipv6 its was disable

This post has been edited by tng55: Mar 17 2023, 11:05 PM

confirmed its Private IP 100.79.XX.XXX

its not Public IP

Hmm it looks like it's not getting beyond TM's own gateway.. have you contacted TM about this issue? If it can ping TM's CGNAT and gateway, but no further, then it's probably a wide spread issue in your general area... And can you include a tracert for IPv6? To Google/Bing/any IPv6 sites?

Including my own tracert to my IPv6 server in OVH SG for reference.



This post has been edited by yenchenje: Mar 18 2023, 01:19 AM

Thanks everyone, issue found, router issue, the Asus AC88 just decided to stop working on IPv4.

Changing a new router fixed the issue.

Router being the issue is definitely a new thing for me, but then again, pretty sure ASUS's router runs quite hot out by default, maybe it was time for it to go as well