I know for ipv6 ACE there is no wildcard mask, so if I want to add three hosts in one statement, for example, which prefix should I use for that network? (network 2001:db8:cafe:1/64, ::1 reserved as default gateway, so I need to exclude ::2, ::3 and ::4 only)

/128 - 1 host -- too few /127 - 2 host -- too few /126 - 4 hosts -- too many

If I use 2001:db8:cafe:1::2/127, it is missing ::4, while 2001:db8:cafe:1::2/126, includes from ::0 - ::3, so I am still missing ::4, plus adding ::0 which I do not want to.

Do I need to then use two ACE or it is possible to group those three hosts in one ACE?

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    – Ron Maupin
    Dec 15 '19 at 3:43

You are not going to be able to do it with one statement. You could use three /128 statements, or one /127 and one /128.

The zero address is the router anycast address, unlike the network address for IPv4, meaning it is probably only going to be a destination address, except for /127 point-to-point links where you use it as the address of one end of the link.

Even with IPv4 wildcard masks, you wouldn't be able to get only those three addresses in one statement.

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