IPv6 BGP on Vultr shows this error:
BGP: 2001:19f0:ffff::1 [Event] Connect start to 2001:19f0:ffff::1 fd 11 BGP: 2001:19f0:ffff::1 went from Idle to Connect BGP: 2001:19f0:ffff::1 open active, local address LOCAL_IPV6_ADDRESS BGP: 2001:19f0:ffff::1 sending OPEN, version 4, my as 64714, holdtime 180, id LOCAL_IPV4_ADDRESS BGP: 2001:19f0:ffff::1 send message type 1, length (incl. header) 53 BGP: 2001:19f0:ffff::1 went from Connect to OpenSent BGP: 2001:19f0:ffff::1 rcv message type 3, length (excl. header) 8 BGP: 2001:19f0:ffff::1 received NOTIFICATION 2/7 (OPEN Message Error/Unsupported Capability) 6 bytes 01 04 00 01 00 01 BGP: 2001:19f0:ffff::1 went from OpenSent to Idle