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09.xx DHCP server issues duplicate leases when using static-ip-mapping

New Contributor III

I have the DHCP pool below defined:

ip dhcp-server pool untrustednetwork 20excluded-address 1 0 0option domain-name-servers routers ntp-servers 100 ascii EST5EDT,M3.2.0,M11.1.0option 101 ascii America/New_Yorkstatic-mac-ip-mapping 20ef.bd8a.d24fstatic-mac-ip-mapping c83a.6b15.57b1static-mac-ip-mapping 8c49.6202.9c95static-mac-ip-mapping 0018.dd0a.0665

Yesterday I started seeing random failures connecting with a new device, and after some troubleshooting realized that it had been given the address even though it is not the device with the MAC address in the static-mac-ip-mapping. Unfortunately I've lost the console output from the `show ip dhcp-server binding` command, but it listed the same address twice, once with the new device's MAC address and once with the static-mac-ip-mapping address.

I then removed that address binding from the system, and rebooted the new device... and it got assigned, which is still a duplicate. I then assumed that the pool must be 'full', and increased its size from 20 to 40 addresses, and removed the .217 binding. A reboot of the new device got a non-duplicate address, and now it works as it should.

From what I can tell, all of the non-statically-mapped addresses in the pool had active bindings, and so when a new device requested an address, the ICX gave it one of the statically-mapped address even though it should not have.