以下config
今回の貴社の申請でのサンプルConfigでございます。
YAMAHA RTXシリーズ

ip route default gateway tunnel 1
ipv6 prefix 1 ra-prefix@lan2::/64
ip lan1 address 192.168.100.1/24
ipv6 lan1 address ra-prefix@lan2::1/64
ipv6 lan1 rtadv send 1 o_flag=on
ipv6 lan2 address ra-prefix@lan2::6f:6c1e:dd00:0/64
tunnel select 1
tunnel encapsulation ipip
tunnel endpoint address 2404:9200:225:100::65
ip tunnel nat descriptor 1
ip tunnel tcp mss limit auto
tunnel enable 1
nat descriptor type 1 masquerade
nat descriptor address outer 1 111.108.30.221
nat descriptor address inner 1 auto
nat descriptor masquerade incoming 1 reject
tftp host any
dhcp service server
dhcp server rfc2131 compliant except remain-silent
dhcp scope 1 192.168.100.2-192.168.100.191/24
dhcp scope option 1 dns=8.8.8.8,8.8.4.4
http revision-up permit on
sshd service on
sshd host key generate *