[AfrIPv6-Discuss] AfrIPv6-Discuss DHCPv6 Server Declaration

[Nishal Goburdhan]

On 14 Jun 2016, at 10:43, DICK,  L. (MR.) wrote:

> Morning
>
> DHCHp6 Server only recognises the subnet declaration of same network 
> with
> the Ethernet Interface of the server. How do I make DHCP6 to issue 
> Ipv6
> addresses of other VLANS or subnets as well? Please assist me. Thank
> you


take it back a step;  you have some infrastructure for your network 
(running ipv4) now, right?
how do you solve your current dhcp issues for ipv4?

as stephen and john said, either your dhcp server needs to be connected 
to each network subnet (which is potentially wasteful, and unnecessarily 
complex), or you need to configure a dhcp relay agent on the network 
(router) devices in the middle, so that they know where to send dhcp 
requests to.

consider:

N1_____R1___
             |
N2_____R2___|
             |____R4____S
N3_____R3___|


so, take the simple picture above;  you have three networks (N1-3) and a 
dhcp server (S) somewhere on your network, separated by some routing 
devices (R).   server S is not on the same logical subnet (ie. not in 
networks 1-3).  on the intermediate routers (R1-3) you’d have to 
configure a dhcp-relay agent, pointing to S, for the interfaces that 
connect to N1-3.

your favourite search engine will help you find the specific commands 
for your hardware, if you search for “dhcp relay agent”.
incidentally, you’d have to do the same thing in IPv4 as well.  so 
this is not a dhcp6 specific issue.

—n.