# Configuring DHCP External Server to Re-Authenticate Auto-Detected Dynamic Subscriber Interfaces

You can use the ip re-authenticate-auto-detect ip-subscriber command to re-authenticate the auto-detected subscribers or Dynamic Subscriber Interfaces (DSIs) created on static and dynamic primary IP interfaces, using the DHCP options when the DHCP external application manages the DSIs following a cold boot. The no version negates the command or restores the defaults.

To enable the IP Subscriber Manager application to re-authenticate the auto-detected subscribers created on static and dynamic primary IP interfaces after a cold boot:

- Issue the ip re-authenticate-auto-detect ip-subscriber command from Interface Configuration or Profile Configuration mode:

host1:vr1(config)#ip re-authenticate-auto-detect ip-subscriber

#### Related Topics

- Preservation of Dynamic Subscriber Interfaces with DHCP External Server Overview
- ip dhcp-external recreate-subscriber-interface