The setting has no effect when using the following command
set interfaces tunnel tun2 address 'fc00:320:f1cd:2::2/64' set interfaces tunnel tun2 disable-link-detect set interfaces tunnel tun2 encapsulation 'ip6ip6' set interfaces tunnel tun2 mtu '1500' set interfaces tunnel tun2 multicast 'enable' set interfaces tunnel tun2 remote 'fc00:320:f1cd:1::1' set interfaces tunnel tun2 source-address 'fc00:320:f1cd:1::4'
After testing, it is found that the tun2 interface has not been enabled for multicast settings, and the Vyos multicast may not be implemented
vyos@vyos:~$ ip addr show tun2
23: tun2@NONE: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
link/tunnel6 fc00:320:f1cd:1::4 peer fc00:320:f1cd:1::1 permaddr 6ea6:345b:fb0a::
inet6 fc00:320:f1cd:2::2/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::f0db:5fff:fe8f:22e7/64 scope link
valid_lft forever preferred_lft forever