Have a think about how this works on a LAN, the whole DHCP process is done using layer 3 broadcasts, but the DHCP client doesn't have an IP address, so as this packet is handled by the TCP/IP stack these packets becomes a layer 2 broadcast frames and...
It may help if you think about NCP and IPCP as sub functions of PPP rather than a separate layer.
When you see a packet trace of PPP traffic you will see:
The PPP negotiations start with LCP doing Config Requests, Ack, Negative Ack, Config Reject, fo...
Generally it is based on a static route and an ACL to define the traffic to encapsulate/encrypt to each remote site.
If you want to do something smarter, like run dynamic routing protocol, then GRE over IPsec is required. The other option is DMVPN ...
+1 on Neno's comment. I recommend this approach too, split the pool between 2 DHCP servers.
There will be no problems if the ping check does not respond for some reason and the address IS actually already in use. Having the same DHCP pool on 2 serv...
Wireshark can't open that .pkt file for some reason.
If you try this with real equipment, 2 LAN hosts and a switch, you will see all sorts of issues. Not only duplicate IP addresses, but the switch will not know how to direct the frames as the same ...