If you want to disable ipv6 by using a global command "set system ipv6 disable" it doesn't work well.
For example, after executing the command "set system ipv6 disable" you can't change MTU on bridge interfaces less than 1280 because the error appears:
[email protected]# set system ipv6 disable [edit] [email protected]# commit Changing IPv6 disable parameter will only take affect when the system is rebooted. [edit] [email protected]# save Saving configuration to '/config/config.boot'... Done [edit] [email protected]# exit exit [email protected]:~$ reboot Are you sure you want to reboot this system? [y/N] y [email protected]# set interfaces bridge br1 mtu 1000 [edit] [email protected]# commit [ interfaces bridge br1 ] VyOS had an issue completing a command. We are sorry that you encountered a problem while using VyOS. There are a few things you can do to help us (and yourself): - Contact us using the online help desk if you have a subscription: https://support.vyos.io/ - Make sure you are running the latest version of VyOS available at: https://vyos.net/get/ - Consult the community forum to see how to handle this issue: https://forum.vyos.io - Join us on Slack where our users exchange help and advice: https://vyos.slack.com When reporting problems, please include as much information as possible: - do not obfuscate any data (feel free to contact us privately if your business policy requires it) - and include all the information presented below Report time: 2022-03-23 06:37:59 Image version: VyOS 1.3.1 Release train: equuleus Built by: Sentrium S.L. Built on: Sat 19 Mar 2022 17:46 UTC Build UUID: *** Build commit ID: *** Architecture: x86_64 Boot via: installed image System type: KVM guest Hardware vendor: *** Hardware model: *** Hardware S/N: *** Hardware UUID: *** Traceback (most recent call last): File "/usr/libexec/vyos/conf_mode/interfaces-bridge.py", line 171, in <module> apply(c) File "/usr/libexec/vyos/conf_mode/interfaces-bridge.py", line 162, in apply br.update(bridge) File "/usr/lib/python3/dist-packages/vyos/ifconfig/bridge.py", line 374, in update super().update(config) File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 1394, in update self.add_ipv6_eui64_address('fe80::/64') File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 687, in add_ipv6_eui64_address self.add_addr(f'{eui64}/{prefixlen}') File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 998, in add_addr self._cmd(f'ip addr add "{addr}" ' File "/usr/lib/python3/dist-packages/vyos/ifconfig/control.py", line 52, in _cmd return cmd(command, self.debug) File "/usr/lib/python3/dist-packages/vyos/util.py", line 161, in cmd raise OSError(code, feedback) FileNotFoundError: [Errno 2] failed to run command: ip addr add "fe80::526b:8dff:feb0:6381/64" dev "br1" returned: exit code: 2 noteworthy: cmd 'ip addr add "fe80::526b:8dff:feb0:6381/64" dev "br1"' returned (out): returned (err): RTNETLINK answers: Invalid argument [[interfaces bridge br1]] failed Commit failed [edit]
To solve this issue you need also to use this command on each bridge interface "set interfaces bridge brX ipv6 address no-default-link-local".
It's unusual behavior the command "set system ipv6 disable".