The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on IP networks whereby a DHCP server dynamically assigns an IP address and other network configuration parameters to each device on a network so they can communicate with other IP networks.
The DHCP protocol provides a mechanism for unprovisioned hosts to request an IP-address and configuration via broadcast requests. Based on available address pools, a DHCP server can provide a DHCP client a time-limited IP address “lease”.
When running in a HA configuration with two nodes, only one of the nodes will actively operate as a DHCP server for those intererfaces that are shared between both systems. Client lease information is sychronized between nodes to ensure that upon link or node failure, the newly active DHCP server will operate with the same information.
The same interface configured as a DHCP server cannot also be configured for DHCP relay.
Naturally the DHCP server cannot itself reside on an interface that is configured as a DHCP client.
A DHCP Server is configured on the network-interface as a host-service of type
The DHCP server supports setting custom options per dhcp-server instance. Custom options are configured as type-value pairs.
Static reservations are supported. When configuring a static assignment within an address pool, the lease will inherit the attributes of the pool (typically this would be the router and domain-server). If you desire to override any of the attributes of the DHCP pool, these can be configured uniquely per static assignment.
Vendor-Specific Information DHCP Options
Being deployed as a router requires the 128T platform to successfully interoperate with a myriad of network elements. These elements can change from customer to customer and use case to use case. To ensure interoperability between these network elements it can become necessary to support Options and Vendor Extensions on top of base functional support.
The two supported Vendor-Specific Information are:
- Vendor-Specific Information Option RFC 2132
- Vendor-Identifying Vendor-Specific Information Option RFC 3925
Two new configuration objects have added to the
vendor-specific-information DHCP option is shown below:
- Code 72, AP Controller Type
An example of two
vendor-identifying vendor-specific information DHCP options are shown below:
- Code 72, Enterprise-Number 122 (SONY), PS Server Addresses
- Code 72, Enterprise-Number 311 (Microsoft), Enable/Disable xBox Live
From within the PCLI, you can execute show network-interface application to show statistics related to the DHCP server as well as any active DHCP client leases.
Active client lease management can be seen in the GUI by navigating to Router > Node > DHCP Server. It is also from within this interface that you can selectively revoke a client lease.