Hello,
My ISP delegates an IPv6 prefix but, unfortunately, it's dynamic and changes weekly. It works though and two LAN interfaces successfully have prefixes. Great!
I would now like to add a ULA to an interface but cannot see a way to add a second IPv6 address if the interface is set dynamically. For testing (please excuse the short ULA), I switched from the interface itself having a prefix delegated to having a ULA:
config ipv6
set ip6-address fdfc:c::40/64
set ip6-allowaccess ping https
set ip6-send-adv enable
set ip6-other-flag enable
config ip6-prefix-list
edit fdfc:c::/64
next
end
config ip6-delegated-prefix-list
edit 1
set upstream-interface "wan1"
set delegated-prefix-iaid 1
set subnet 0:0:0:1::/64
set rdnss-service default
next
end
end
I have (accidentally) stumbled upon a solution. It seems to work but is this actually valid configuration?
Many thanks for reading
Hello,
Thank you for using the Community Forum. I will seek to get you an answer or help. We will reply to this thread with an update as soon as possible.
Thanks,
Hello,
We are still looking for someone to help you.
We will come back to you ASAP.
Thanks,
To add an IPv6 Unique Local Address (ULA) to an interface already configured with prefix delegation on a FortiGate:
shell
config system interface
edit "port5" <----- Replace "port5" with your actual interface name.
shell
config ipv6
set ip6-address fdxx:xxxx:xxxx::1/64 <----- Replace with your ULA.
end
shell
end
Hi Anthony,
Thanks for getting back to me, it's appreciated.
If an interface is configured to use a delegated prefix, trying to set ip6-address returns an error:
(ipv6) # set ip6-address fdfc:c::40/64
Can't change dynamic IPv6.
Command fail. Return code -651
Is it actually possible to add a ULA to an interface with prefix delegation?
Thanks again
Hello,
I really hope we will find an answer and fix your issue :)!
I will try to find an expert for your question, and will come back to you ASAP.
Regards,
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