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EjgtePiraat

Member

Registered: 2024-04-23

Posts: 6

ipv6 adresses not reachable

Hi,

For some reason I cannot reach ipv6 addresses from my computer. For example:

[dadai@localhost ~]$ ping -vvv -6 2001:4860:4860::8888
ping: sock4.fd: -1 (socktype: 0), sock6.fd: 3 (socktype: SOCK_DGRAM), hints.ai_family: AF_INET6

ai->ai_family: AF_INET6, ai->ai_canonname: '2001:4860:4860::8888'
ping: connect: Network is unreachable

On NetworkManger.conf I do have:

NetworkManager.conf
[connection]
ipv6.ip6-privacy=2
[Network]
IPv6PrivacyExtensions=yes

I am using NetworkManager with systemd-resolved. Afaik, ipv6 used to work, but maybe that was more than a year ago.
I have no clue how to debug this problem, so any help is greatly appreciated.

Last edited by EjgtePiraat (2025-05-15 21:08:00)

-thc

Member

Registered: 2017-03-15

Posts: 873

Re: ipv6 adresses not reachable

The first step would be to check if your interface has an (globally routable) IPv6 address

ip a
ip -6 r

EjgtePiraat

Member

Registered: 2024-04-23

Posts: 6

Re: ipv6 adresses not reachable

I get:

[dadai@localhost ~]$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host noprefixroute
       valid_lft forever preferred_lft forever
2: enp4s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
    link/ether 88:a4:c2:54:0a:eb brd ff:ff:ff:ff:ff:ff
    altname enx88a4c2540aeb
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether c2:73:f8:68:4d:dc brd ff:ff:ff:ff:ff:ff permaddr 2c:6d:c1:0c:65:c5
    inet 145.116.176.207/22 brd 145.116.179.255 scope global dynamic noprefixroute wlan0
       valid_lft 6900sec preferred_lft 6900sec
    inet6 fe80::4b16:9a68:a1db:e48f/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
[dadai@localhost ~]$ ip -6 r
fe80::/64 dev wlan0 proto kernel metric 1024 pref medium

Not sure what any of that means.

Last edited by EjgtePiraat (Yesterday 12:20:33)

-thc

Member

Registered: 2017-03-15

Posts: 873

Re: ipv6 adresses not reachable

It means IPv6 is enabled on your WiFi interface (it has a link-local address beginning with "fe80") but you get no globally routable IPv6 address from your router and/or your ISP. Did those change recently?

cryptearth

Member

Registered: 2024-02-03

Posts: 1,422

Re: ipv6 adresses not reachable

145.116.128.0/18 is assigned to Radboud Universiteit Nijmegen
have you contacted the IT guys?

EjgtePiraat

Member

Registered: 2024-04-23

Posts: 6

Re: ipv6 adresses not reachable

Nope, this is the connection from my university, so no recent connection as far as I am aware. I also tried using a vpn (through ultra.cc) with the same result. Home router also doesn't make a difference.

-thc

Member

Registered: 2017-03-15

Posts: 873

Re: ipv6 adresses not reachable

If your provider (university) doesn't support IPv6 (and your router does) there's not much your can do on that very fact.

Alternatively there are IPv6-over-IPv4 tunnel services and VPN provider with full IPv6 support.

And BTW: the "IPv6PrivacyExtensions=yes" statement is for systemd-networkd - not NM.

Last edited by -thc (Yesterday 18:11:50)