is mtu under 1250 a strong requirement in mode 1?

[eebssk1]

Currently I'm tuneling non-popular vpn solution with IPV6 enabled. The minimal mtu required by ipv6 is 1280. Since the wiki says 1250 is the safe value under mode 0. I'm wondering is ipv6 can be tunneled without any problem in mode 1?

[wangyu-]

you are confused by the multiple meanings of MTU. "min mtu required by ipv6" is 1280 means ipv6 need to support at lease 1280. Sending a packet of 500 is, of course, supported by ipv6.

[eebssk1]

you are confused by the multiple meanings of MTU. "min mtu required by ipv6" is 1280 means ipv6 need to support at lease 1280. Sending a packet of 500 is, of course, supported by ipv6.

The problem is the mimimal TAP/TUN interface mtu for ipv6 to enable on it is 1280. So it means bulk traffic are mostly always 1280 when being transferred out. Thats where i'm worrying.

[eebssk1]

Also I'm already trying this way. It seems no problem currently. So I consider it is safe?

[eebssk1]

Update: Mode I'm referering is mode 1,not mode 0.