I am troubleshooting DHCP between server and client (both Cisco IOS). I have discovered, that server sees client under completely nosensical client identification:
R1#sh ip dhcp binding
Bindings from all pools not associated with VRF:
IP address Client-ID/ Lease expiration Type
10.0.6.3 0063.6973.636f.2d30. Apr 01 2001 10:40 PM Automatic
Yes, the client id server sees is "3062.302e.6332.3838.2e31.3637.312d.4661.30" instead of little more conventional "00b0.c288.1671". What's up here? This thing makes manual binding impossible, as that long number is not accepted in "client-identifier" on server.
Edit: No, I wasn't cut'n'pasting properly, that long client-id can be entered into pool configuration. So that solves the problem, and the only think that remains unanswered for me is what were Cisco thinking, when they decided that client-id is going to be this kind of crazy stuff instead of plain MAC.