Forum Discussion
Matthew Jados
Nov 30, 2018Copper Contributor
DHCPv6 and specifying IP exlcustions for a default /64 scope
Hello,
I am currently in the process of setting up dhcpv6 on my AD server and I noticed that when you specify the dhcpv6 scope you are restricted to only setting a /64 prefix. (This is way more IP's then I need for the dhcpv6 scope) I want to only hand out a /113 specific range.
I noticed the only way to do this is to exclude a hole lot of IP's in the /64.
How do I come up with the exclusion list so that I am only handing out that specific /113 prefix that I have?
Or would it just be better to use unique /64s for each vlan?
Example:
vlan1 - 2001:1900:3000:4::0/64
vlan2 - 2001:1900:3000:5::0/64
vlan3 - 2001:1900:3000:6::0/64
I look forward to hearing peoples thoughts
Thanks in advance
- vzalexisCopper ContributorYou have to use a pair of exclusion ranges per scope. I'm sure if you've looked up to the IPv4 section, you'd have noticed "inclusion ranges". I submitted a request to have Microsoft include it back in 2010 but they declined.
Let's say you're trying to dole out 2001:1900:3000:4:abcd:dead:beef:0/113
Youd' set:
Exclusion 1 = 2001:1900:3000:4:: to 2001:1900:3000:4:abcd:dead:beef:0
Exclusion 2 = 2001:1900:3000:4:abcd:dead:beef:ffff to 2001:1900:3000:4:ffff:ffff:ffff:ffff
To be exact, it would technically be:
Exclusion 1 = 2001:1900:3000:4:: to 2001:1900:3000:4:abcd:dead:beee:ffff
Exclusion 2 = 2001:1900:3000:4:abcd:dead:bef0:0 to 2001:1900:3000:4:ffff:ffff:ffff:ffff
to include the first and last address in the range (if you really wanted the scope to start at the 0th address) but normally you don't result in "beee:ffff" it just makes doing the math harder. Something here may help.
or also reach out to experts over here.
https://social.technet.microsoft.com/Forums/windowsserver/en-US/home?forum=ipv6
https://social.technet.microsoft.com/Forums/windowsserver/en-US/home?forum=winserveripamdhcpdns