Closed waybeforenow closed 4 years ago
The [prefix_*] defiinitons are made for prefix delegation - PD. See https://dhcpy6d.ifw-dresden.de/documentation/config/prefixes/.
What OS are you using? I see the same behaviour on Fedora Linux for example which automatically uses a /128.
As far as I understand the DHCPv6 RFC 3315 there is no way to tell the prefix length to the clients.
Thanks, I think I now understand why prefix delegation isn't what I'm trying to achieve (though the documentation doesn't explain why prefix delegation is useful; maybe including a link to the Wikipedia article or similar would be a helpful pointer).
What OS are you using?
This is a testing network for a VPN I intend to deploy sometime in the future. For testing purposes, the network has three hosts running different operating systems. These hosts are bridged
dhcpcd
to obtain an IPv6 addressBoth my laptop and the embedded device receive /128 addresses.
As far as I understand the DHCPv6 RFC 3315 there is no way to tell the prefix length to the clients.
I'm having some trouble understanding this, since I come from IPv4-land where it would make no sense to dynamically assign an address with a /32 netmask. How exactly am I supposed to route to anything with a /128 address? My ostensible default gateway on the VPN has a static address of 2001:db8:beef::1/64
; I'm unable to ping it.
I have a macOS here which has this ifconfig:
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
options=50b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV,CHANNEL_IO>
ether 68:5b:35:94:32:5a
inet6 fe80::13:d6e8:bd49:241a%en0 prefixlen 64 secured scopeid 0x7
inet 172.16.106.135 netmask 0xffff0000 broadcast 172.16.255.255
inet6 2001:638:90a:1600:e917:fd7:bbb6:a336 prefixlen 128 dynamic
nd6 options=201<PERFORMNUD,DAD>
media: autoselect (1000baseT <full-duplex,flow-control>)
status: active
Your local router should be requested automatically by your client.
Edit: What does a netstat-rn
on your macOS show you?
I guess there is no way to give the client a prefix-length using DHCPv6 per the RFC, and I figured out how to route to a /128
address, so all is well. I'll close this issue now.
Hi, thanks for building and maintaining this tool! It's very useful.
I would like some advice on how to configure the prefix length of IPv6 addresses that
dhcpy6d
assigns.I'm using
dhcpy6d
to dynamically assign IP addresses to clients on a VPN. They need to all be in the same logical network, so they should all have some address that looks like2001:db8:beef::x/64
. So I wrote this configuration:And I was able to get a dynamically assigned address using this config, but it was
2001:db8:beef::1000/128
- no good. But it makes sense, since I never configured a prefix length. So I added a prefix and an associated class to advertise it:(Btw, I needed to put a
range
in my prefix even though I only needed one prefix - might be worth adding a separatecategory
for this type of configuration.)When I install this configuration, I'm still getting
2001:db8:beef::1000/128
instead of2001:db8:beef::1000/64
. I've been playing around with the configuration some more, but I haven't been able to fix this. Is it possible to assign a/64
address usingdhcpy6d
?