We have two DHCP servers, the OLD server and the NEW server. We'd like to migrate to the NEW server, but we cannot get it consistently deliver IP addresses to our various subnets.
We have all of the appropriate IP-Helpers in our switches. The behavior is as follows:
We are using Microsoft Server 2016 with Microsoft DHCP Server. The server sits on ESXi host. (different host)
1. We turn off the OLD DHCP server and turn on the NEW DHCP server. Scopes are enabled.
2. In some cases, users will get new IPs right away.\
3. In some cases, users never get an IP, they get a 169.254.x.x address.
4. In all cases, if we switch NICs on the user's computer, they will get an IP. For example switching from the docking station NIC to the laptop NIC will always give an IP from the NEW server.
5. We can usually find the following message in the logs: "Your computer was not assigned an address from the network (by the DHCP Server) for the Network Card with network address 0xF4D108E45BA6. The following error occurred: 0x79. Your computer will continue to try and obtain an address on its own from the network address (DHCP) server."