dhcpcd-discuss

Hi Shweta

On 11/05/2019 18:16, Shweta Kalyani wrote:
> Is there a way to hint in the DHCPv6 request the desired prefix length 
> that the client needs when requesting for IA_PD addresses?

dhcpcd.conf(5) says this:
     ia_pd [iaid [/ prefix / prefix_len] [interface [/ sla_id [/ 
prefix_len [/
             suffix]]]]]
             Request a DHCPv6 Delegated Prefix for iaid.  This option 
must be
             used in an interface block.  Unless a sla_id of 0 is assigned
             with the same resultant prefix length as the delegation, a 
reject
             route is installed for the Delegated Prefix to stop 
unallocated
             addresses being resolved upstream.  If no interface is 
given then
             we will assign a prefix to every other interface with a sla_id
             equivalent to the interface index assigned by the OS. 
Otherwise
             addresses are only assigned for each interface and sla_id. 
 Each
             assigned address will have a suffix, defaulting to 1.  If the
             suffix is 0 then a slaac address is assigned.  You cannot 
assign
             a prefix to the requesting interface unless the DHCPv6 server
             supports RFC6603 Prefix Exclude Option.  dhcpcd has to be 
running
             for all the interfaces it is delegating to.  A default 
prefix_len
             of 64 is assumed, unless the maximum sla_id does not fit.  In
             this case prefix_len is increased to the highest multiple of 8
             that can accommodate the sla_id.  sla_id is an integer 
which must
             be unique inside the iaid and is added to the prefix which 
must
             fit inside prefix_len less the length of the delegated prefix.
             You can specify multiple interface / sla_id / prefix_len per
             ia_pd, space separated.  IPv6RS should be disabled 
globally when
             requesting a Prefix Delegation.


So you could write this:

interface eth0
	ia_pd 1//56 eth1/1/64 eth2/2/64

Hope this helps, and if you could suggest a wording change to the above 
so it's easie to read,  it would be appreciated!

Roy