Cisco IP 7940 Configuration Manual page 9

Step2. Enable DHCP Server on MyPBX.
Login MyPBX web interface, go to System  Network Preferences  DHCP
Server, enable DHCP server.
Step3. Configure phones on MyPBX Auto-Provision page.
1) Login MyPBX web interface, go to PBX  Extensions  Phone Provisioning
click Add Phone.
Cisco IP Phone Configuration Guides
Figure 3-2
Figure 3-3
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