IPV6 not working. I can ping the gateway but not any other ipv6

July 29, 2019 815 views
Networking IPv6 CentOS

I followed every step on https://www.digitalocean.com/docs/networking/ipv6/how-to/enable/

But I can’t still ping6 2001:4860:4860::8888

It says that the network is unreachable.

When I ping the ipv6 gateway, although, it’s fine. The gateway is returning the packets.

2 Answers

Hello!

Can you see the network interface when you’re logged on the droplet via ssh? ifconfig should list you all the network interfaces and you can double check everything. If you have rebooted the network, you wont need to restart the network service, but you can give it a try.

Let me know how it goes.

Alex

  • Hey Alex,

    Yes, I can see the interfaces, I already added the lines the tutorial describes on eth0. As follows:

    # Created by cloud-init on instance boot automatically, do not edit.
    #
    BOOTPROTO=none
    DEFROUTE=yes
    DEVICE=eth0
    GATEWAY=139.59.0.1
    HWADDR=9a:c4:62:0f:61:b0
    IPADDR=139.59.15.43
    IPADDR1=10.47.0.8
    MTU=1500
    NETMASK=255.255.240.0
    NETMASK1=255.255.0.0
    ONBOOT=yes
    TYPE=Ethernet
    USERCTL=no
    IPV6INIT=yes
    IPV6ADDR=2400:6180:100:d0::2f:6001/64
    IPV6_DAFAULTGW=2400:6180:100:d0::1
    DNS1=2001:4860:4860::8844
    DNS2=2001:4860:4860::8888
    DNS3=209.244.0.3
    
    

    I have an eth1 interface too. I tried to change the settings there, but apparently it was not effective (I guess it’s for the private ip and internal network of my droplets), so I setted back to the original version of the file.

    I’ve restarted the network and rebooted the droplet twice for each interface change.

    Also, I suspected it was something related to ip6tables, but I changed the configs to accept all the traffic, and it didn’t helped.

    • If you’re sure that all the steps are done, you can always perform a traceroute to see if there is a problem with the connection.

      You can use the following commands in order to perform the traceroute for the IPv6 address.

      Mac / Linux: traceroute6 2a00:1450:400a:804::2004
      Windows: tracert -6 2a00:1450:400a:804::2004
      

      You can also use any website which offers traceorute, like https://tools.keycdn.com/ipv6-ping

      Check for packet loss on any of the hops.

      Let me know how it goes.

      Alex

      edited by MattIPv4
      • When I try to execute the traceroute from within the droplet, it just returns “connect: The network is unreachable”, right away.

        From the keycdn tool, it is not able to connect to the server from anywhere in the world, except from Bangalore, where the server is located. Every other origin have 100% packet loss when it gets to the last node of the route.

        • A lot of ISPs will ignore INCP requests and also wont have IPv6 configured along the way, but I think you might want to check this with DigitalOcean over a support ticket so their experts can check this for you as well.

          Alex

          edited by MattIPv4
          • I posted a support ticket like 6 hours ago. I’m still waiting for them.

            Anyway, thank you very much

IPv6 configuration is usually straight forward, I guess something might be happening here, so DigitalOcean should be able to shed some light on this.

In the meantime if I have other suggestions, I’ll let you know. Hopefully this will be sorted soon.

Alex

edited by MattIPv4
  • It was a typo:

    IPV6_DAFAULTGW=2400:6180:100:d0::1

    when it shoud be

    IPV6_DEFAULTGW=2400:6180:100:d0::1

    I don’t believe I couldn’t see it… :(

    Anyway, thanks a lot for the help!

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