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dramm

Member

Registered: 2017-07-17

Posts: 13

[SOLVED] Can ping IPv6 devices locally but not on WAN (aka google.com)

I solved the issue by switching to netctl, instead of NetworkManager.
If anyone is interested in debugging this I'm open to reinstalling NetworkManager again.

I can't ping google.com (100% packet loss) and https://ipv6-test.com fails.
However, I can ping my phone which is in the same network using its IPv6 address that shows on https://ipv6-test.com.
Since the ping is +120ms I assume the connection is going through the WAN and not staying on the LAN, but I'm not sure how this works.

Yesterday I was trying to debug this and after checking the iptables rules I connected to the router using WiFi, I could ping google.com and pass https://ipv6-test.com
Today it doesn't work while on WiFi either. Unfortunately, I don't have the output of ip route command from yesterday and I'm clueless about what might have happened.

I saw these two topics relating to issues with dual boot and an Intel driver bug, but my CPU is AMD.
Even though the CPU is AMD it seems the NIC is Intel. I disabled Wake-on-LAN and also tried the normal kernel version 6.1.9 (was using zen 6.1.9 before). Fastboot is disabled
I do have dual boot with Win10 and in Windows I can pass the test and ping google.
https://bbs.archlinux.org/viewtopic.php?id=263444
https://bbs.archlinux.org/viewtopic.php?id=281067

I don't know much about networking, but my first guess was to check the firewall rules.
Let me know if there are any other files that can help with debugging this issue.

edit: Forgot to mention I'm using NetworkManager

$ip -6 route show #wifi off

::1 dev lo proto kernel metric 256 pref medium
2804:7f4:c1aa:a453::/64 dev enp5s0 proto ra metric 100 pref medium
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev enp5s0 proto ra metric 100 pref high
fe80::/64 dev enp5s0 proto kernel metric 1024 pref medium
default proto ra metric 20100 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev enp5s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev enp5s0 weight 1 

~ ip -6 route show #wifi connected
::1 dev lo proto kernel metric 256 pref medium
2804:7f4:c1aa:a453::/64 dev enp5s0 proto ra metric 100 pref medium
2804:7f4:c1aa:a453::/64 dev wlp4s0 proto ra metric 600 pref medium
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev enp5s0 proto ra metric 100 pref high
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 proto ra metric 600 pref high
fe80::/64 dev enp5s0 proto kernel metric 1024 pref medium
fe80::/64 dev wlp4s0 proto kernel metric 1024 pref medium
default proto ra metric 20100 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev enp5s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev enp5s0 weight 1 
default proto ra metric 20600 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev wlp4s0 weight 1

ip6tables.rules

# Generated by ip6tables-save v1.8.8 on Mon Jan 30 18:17:39 2023
*mangle
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
-A PREROUTING -m rpfilter -j ACCEPT
-A PREROUTING -j DROP
COMMIT
# Completed on Mon Jan 30 18:17:39 2023
# Generated by ip6tables-save v1.8.8 on Mon Jan 30 18:17:39 2023
*filter
:INPUT ACCEPT [6:564]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [518:151796]
-A INPUT -p ipv6-icmp -m icmp6 --icmpv6-type 128 -m conntrack --ctstate NEW -j ACCEPT
-A INPUT -s fe80::/10 -p ipv6-icmp -j ACCEPT
-A INPUT -p udp -m udp --sport 547 --dport 546 -j ACCEPT
COMMIT
# Completed on Mon Jan 30 18:17:39 2023
# Generated by ip6tables-save v1.8.8 on Mon Jan 30 18:17:39 2023
*raw
:PREROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [518:151796]
-A PREROUTING -m rpfilter -j ACCEPT
-A PREROUTING -j DROP
COMMIT
# Completed on Mon Jan 30 18:17:39 2023

Last edited by dramm (2023-02-02 19:38:53)

dramm

Member

Registered: 2017-07-17

Posts: 13

Re: [SOLVED] Can ping IPv6 devices locally but not on WAN (aka google.com)

After a system update and a reboot IPv6 is working properly while on WiFi. I can ping google.com and pass the ipv6 test.
It seems the default routes for the WiFi interface are different than the routes for the wired interface.
I'm not sure what is changing the routes though.

~ ip -6 route show             
::1 dev lo proto kernel metric 256 pref medium
2804:7f4:c1aa:a453::/64 dev enp5s0 proto ra metric 100 pref medium
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev enp5s0 proto ra metric 100 pref high
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 proto ra metric 600 pref high
fe80::/64 dev enp5s0 proto kernel metric 1024 pref medium
fe80::/64 dev wlp4s0 proto kernel metric 1024 pref medium
default via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 proto ra metric 600 pref high
default proto ra metric 20100 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev enp5s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev enp5s0 weight 1 

~ traceroute -6 google.com 
traceroute to google.com (2800:3f0:4001:824::200e), 30 hops max, 80 byte packets
 1  2804:7f4:c2ad:8479:860b:bbff:fe1c:efa8 (2804:7f4:c2ad:8479:860b:bbff:fe1c:efa8)  3.154 ms  3.456 ms  4.025 ms
 2  2804:7f4:2000:1::be (2804:7f4:2000:1::be)  7.123 ms  7.503 ms  7.818 ms
 3  2804:7f4:2000:1000::8b7 (2804:7f4:2000:1000::8b7)  7.818 ms  7.811 ms  7.805 ms
 4  2001:12e0:100:3024:a008:3024:a006:1 (2001:12e0:100:3024:a008:3024:a006:1)  6.703 ms 2001:12e0:100:3024:a006:3024:a008:12 (2001:12e0:100:3024:a006:3024:a008:12)  7.076 ms 2001:12e0:100:3024:a002:3024:a008:2 (2001:12e0:100:3024:a002:3024:a008:2)  7.488 ms
 5  2001:12e0:100:3003:a002:3024:a005:0 (2001:12e0:100:3003:a002:3024:a005:0)  8.162 ms  8.442 ms  8.435 ms
 6  * * 2001:12e0:100:3003:a002:3020:a002:13 (2001:12e0:100:3003:a002:3020:a002:13)  47.074 ms
 7  * * *
 8  * * *
 9  * * *
10  2800:3f0:8062::1 (2800:3f0:8062::1)  47.240 ms * 2800:3f0:802b::1 (2800:3f0:802b::1)  46.914 ms
11  2800:3f0:4001:824::200e (2800:3f0:4001:824::200e)  47.170 ms * *

edit: A couple minutes later the routes updated but IPv6 was still fine (with WiFi connected)

~ ip -6 route show                
::1 dev lo proto kernel metric 256 pref medium
2804:7f4:c1aa:a453::/64 dev enp5s0 proto ra metric 100 pref medium
2804:7f4:c1aa:a453::/64 dev wlp4s0 proto ra metric 600 pref medium
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev enp5s0 proto ra metric 100 pref high
2804:7f4:c2ad:8479::/64 via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 proto ra metric 600 pref high
fe80::/64 dev enp5s0 proto kernel metric 1024 pref medium
fe80::/64 dev wlp4s0 proto kernel metric 1024 pref medium
default proto ra metric 600 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev wlp4s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev wlp4s0 weight 1 
default proto ra metric 20100 pref high
	nexthop via fe80::860b:bbff:fe1c:efa8 dev enp5s0 weight 1 
	nexthop via fe80::b2be:76ff:fe09:854c dev enp5s0 weight 1

Last edited by dramm (2023-02-02 14:53:04)