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23.1 Legacy Series / Re: Can't start DHCPv6/radvd
« on: June 26, 2023, 02:52:29 am »
Final Update: All is now working.
Summary: If you disable IPv6 while DHCPv6 is enabled, the Web UI is bugged and won't let you configure other DHCPv6 settings because the "Enable DHCPv6 on $interface interface" box is checked. Unfortunately, this box is hidden, so you won't be able to uncheck it from UI.
Steps to resolve the issue if you've disabled IPv6 with DHCPv6 still enabled/running:
There's definitely a bug in the Web UI, because all of this should not be necessary to get in this exact order. Specifically, if you need to disable DHCPv6 service for an interface, that box needs to be available in the UI, which it's not.
Summary: If you disable IPv6 while DHCPv6 is enabled, the Web UI is bugged and won't let you configure other DHCPv6 settings because the "Enable DHCPv6 on $interface interface" box is checked. Unfortunately, this box is hidden, so you won't be able to uncheck it from UI.
Steps to resolve the issue if you've disabled IPv6 with DHCPv6 still enabled/running:
- SSH to the machine and run "ifconfig | grep ::1". You should see a line returned, which is from the lo0 interface
- Run these to get rid of that stuck config:
ifconfig lo0 inet6 ::1 delete
ifconfig lo0 inet6 fe80::1 delete - Now go to Interfaces: [LAN] and set "IPv6 Configuration Type to "Static IPv6"
- Under the "Static IPv6 Configuration" block, set the IP address to ::1 and dropdown 128. Click Save
- Now you should be able to go to Services: DHCPv6: [LAN]. Uncheck "Enable DHCPv6 server on LAN interface. Click Save". All of the prior steps were to get this checkbox to even be available in the UI.
- Go back to Interfaces: [LAN]. Now you can set IPv6 Config Type to "Track Interface" and point it to the WAN below. I also had to check "Allow manual adjustment of DHCPv6 and Router Advertisements" (or DHCPv6 service wouldn't start again). Save again.
- Reboot - This was crucial. Under Services: DHCPv6: [LAN], my available range had an error: No available address range for configured interface subnet size. Reboot fixed this.
- Finally, I could go to Services: DHCPv6: [LAN] and "Enable DHCPv6 server on this interface". I set the Range from "::" to "::ffff" according to https://homenetworkguy.com/how-to/configure-ipv6-opnsense-with-isp-such-as-comcast-xfinity/
- Click Save and validate DHCPv6 is now running as expected.
There's definitely a bug in the Web UI, because all of this should not be necessary to get in this exact order. Specifically, if you need to disable DHCPv6 service for an interface, that box needs to be available in the UI, which it's not.