ざっと下り 200Mbps くらい出てるので満足
IPv6 addresses are allocated as ranges, which you can choose to distribute and further route yourself. These ranges can only be allocated by our support team. Please open a Support Ticket and request an IPv6 range for this Linode.
とかかいてあるのでチケット立てれば行けそうだな
例の Grub の話は UEFI 環境のみ影響するらしいので Legacy Boot な KVM サーバーとかは関係ないっぽい
System hangs after POST and the grub menu never loads after applying the RHSA-2020:3216 or RHSA-2020:3217 - Red Hat Customer Portal https://access.redhat.com/solutions/5272311