dhcpcd-discuss

Re: DHCPD server IPv6 address selection

Roy Marples

Sun Apr 26 21:23:21 2020

On 16/03/2020 13:36, Roy Marples wrote:
Hi Dusan

On 16/03/2020 12:47, Mudric, Dusan (Dusan) wrote:
What does DHCPv6 server do when the phone detects the assigned address is duplicated?

  * If the address is statically assigned, is the server going to send the same
    address, which cannot be used since it is duplicated?
  * If the address is from a pool, is the server going to send a new address?
  * Any other option?

There has been this long standing comment at the top of dhcp6.c

https://roy.marples.name/cgit/dhcpcd.git/tree/src/dhcp6.c#n29
/* TODO: We should decline dupliate addresses detected */

Basically, DHCPv6 is made complicated by having many addresses and I've never gotten around to actually trying to decline some of the addresses.

Well, I've finally gotten around to fixing it.
Tested against WIDE dhcp6 server on NetBSD and comitted here:
https://roy.marples.name/cgit/dhcpcd.git/commit/?id=9c817dc5a5567ca735a713a76f5b62f8bb954ea9

AFAIK dhcpcd is the only open source DHCPv6 client that now does this :)

Roy

Follow-Ups:
Re: DHCPD server IPv6 address selectionShahid Mahmood
References:
DHCPD server IPv6 address selectionMudric, Dusan (Dusan)
Re: DHCPD server IPv6 address selectionRoy Marples
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