Understanding DHCP-relay

[Stril]

Hi!

For hours now, I am trying to really understand how to configure:
- a central Linux DHCPd-server
- satellite DHCP-relays

...but I still did not reach my goal...

The main problem is:
- How does DHCPd "assign" the right subnet-zone to the relay-agent?

If the DHCPd-server owns an interface in the subnet, everything is clear, but how is it for remote networks?

The second problem:
Normally, I am using two DHCPd-servers in a failover-config. Can a DHCP-relay be configured to use two DHCPd?

Thank you and best wishes
Stril

 

[kubn2]

The main problem is:
- How does DHCPd "assign" the right subnet-zone to the relay-agent?

Relay agent putting his own ip address (address of the interface that will be default gateway for host looking for dhcp server) in GIADDR field. So when DHCP recive such request he looks into GIADDR field to determinate for which subnet he need to provide an address.

Can a DHCP-relay be configured to use two DHCPd?

Yes.