DHCP server

Overview

The dynamic host configuration protocol (DHCP) enables a server to automate the assignment of IP addresses, and other networking settings, to host computers. The DHCP server on the switch provides both IPv4 and IPv6 support and is independently configurable on each VRF.

Key features

  • Supports multiple address pools and static address bindings.

  • Supports DHCP options, enabling the server to provide additional information about the network when DHCP clients request an address.

  • Supports BOOTP to distribute boot image files using an external TFTP server.

  • VRF aware, meaning that DHCP client requests received on an interface are processed by the DHCP server instance configured for a VRF. DHCP server responses are forwarded to clients on the VRF.

  • Supports external storage of lease information on a remote host. This enables the DHCP server to restore lease information after a reboot or a failure. Lease information is stored in a flat file on the configured external device. It is important that the external device provide persistent external storage to allow restoration of lease information. If external storage is not configured, then after a failure or reboot, all existing lease information is lost.

  • Supports VSX. In a VSX setup, one switch acts as primary and the other switch acts as secondary. The DHCP server is active only on the primary switch. After a failover, the DHCP server is enabled based on the state and role of the switch. The state of the DHCP server indicates the operational state of the server. VSX synchronization supports DHCPv4 and DHCPv6 server, including external storage configurations. For more information on VSX support, see the ArubaOS-CX Virtual Switching Extension (VSX) Guide.

DHCP relay interoperation

DHCP server and DHCP relay cannot both be active on interfaces belonging to the same VRF.