2 ipv6 addresses - which one

Discussion in 'Installation/Configuration' started by Tastiger, May 10, 2021.

  1. Tastiger

    Tastiger Member HowtoForge Supporter

    Just finalizing my move to a new server and about to move over my domains but just noticed I am showing 2 ipv6 entries on the local network :-
    Which one do I use in sites?
    Thanks in advance
  2. ahrasis

    ahrasis Well-Known Member HowtoForge Supporter

    It should be empty or use asterisk too right?

    In any event I normally use first 16 digit as basic, followed by ::123 where 123 normally I put the same as my ipv4 last 3 digit; and I add it in System > Server IP Addresses.

    This will eventually allow user to select the server ipv6 from the drop down menu.
    Last edited: May 10, 2021
  3. Tastiger

    Tastiger Member HowtoForge Supporter

    You can already choose ipv6 address from the drop down as long as it is set in "server IP addresses" in the "System" tab. IPV6 Address line doesn't have an asterisk, at least in ISPConfig Version: 3.2.4

    From what I can gather one is automatically configured address based on your Ethernet MAC address. That is the address that will be used to connect to websites and other outgoing connections. It will change over time to maintain your privacy and make you harder to track. which is not the one we want.

    It gets worse if I use I use the command
    I end up with this....
  4. Th0m

    Th0m ISPConfig Developer Staff Member ISPConfig Developer

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  5. ahrasis

    ahrasis Well-Known Member HowtoForge Supporter

    I forget to mention or ask, did you set fixed ipv6 in your netplan yaml file? I did this for my server too as it is mentioned in the minimal debian or ubuntu server tutorial.
    Tastiger likes this.
  6. Tastiger

    Tastiger Member HowtoForge Supporter

    I haven't, but it sounds like it may be a good idea, I didn't see that in the tutorial so I only have ipv4 set.
    Can you post an example of your netplan yaml ? There are examples online but it would be good to see one that is in a working environment close to my own setup.

    I have also seen a couple of other sources that suggest the the IPV6 address that contains the :fe: entry is the correct one to use.
  7. ahrasis

    ahrasis Well-Known Member HowtoForge Supporter

    Sorry, I think it is in the manual, not tutorial. In any event, I think you also need to add the fixed ipv6 in /etc/hosts as well.

    So my steps are something like:

    1. Run ip a and get the first 16 digit part (sometimes less digit) of the global ipv6.

    2. Add the same in the hosts file:
    # Fixed Internal IP   example.domain.tld
    2001:8003:5138:8600::109  example.domain.tld
    Note: In multi server setup, add other server fixed ipv4 and ipv6 in addition to the above.

    3. Add the same in my netplan yaml file and apply:
    # This file describes the network interfaces available on your system
    # For more information, see netplan(5).
     version: 2
     renderer: networkd
         dhcp4: no
         dhcp6: no
           - 2001:8003:5138:8600::109/64
         gateway6: fe80::1
            - 2606:4700:4700::1111
            - 2606:4700:4700::1001
            - 2001:4860:4860::8888
            - 2001:4860:4860::8844
    4. Run ip a again to confirm.

    5. Finally test access using either the fixed ipv4 or the fixed ipv6 (even server to server) before adding and using it inside ISPConfig UI.

    I think that is it and hope it will help.
    Last edited: May 11, 2021
  8. Tastiger

    Tastiger Member HowtoForge Supporter

    Many thanks for that excellent example.
    One further question though, should the IPV6 entry in hosts not be :-
    Code: server1.example.com server1
    2001:8003:5138:8600::109 server1.example.com server1
    ... or does the IPV4 entry take care of the hostname so it isn't needed with the IPV6 address?
  9. ahrasis

    ahrasis Well-Known Member HowtoForge Supporter

    I don't manage my hosts file that way, as in it, just above the # Fixed Internal IP I have something like this:
    # FQDN hostname -f    wbs001.example.com  mls001.example.com  fls001.example.com dbs001.example.com dns001.example.com  s001
    I think the reason was for me to know which service I enabled in the particular server (e.g. s001) but in your case, I would do the same that is " server1.example.com server1" instead of adding the hostname (e.g. server1) at the end of the fixed ipv4 or ipv6.
    Last edited: May 12, 2021
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  10. till

    till Super Moderator Staff Member ISPConfig Developer

    I do not agree with that, I'll use asterisk on all of my multiserver nodes. Disabling asterisk on multiserver nodes makes not much sense, they are no different from a single server node in any way in this regard.

    The field displays the IP addresses of the server which you selected in the 'server' field above the IP address only, so duplicating the server name here gives no benefits as the field will not show IP addresses from other nodes anyway. so you can not select an IP from server one in a website that's located on server 2.
    Tastiger and Th0m like this.
  11. ahrasis

    ahrasis Well-Known Member HowtoForge Supporter

    Thank you for the clarifications.

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