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DHCP

These models manage how the DHCP server built into DRP. They determines what IP addresses it can hand out to which systems, what values to set for DHCP options, and how to handle DHCP requests at various points in the lifecycle of any given DHCP lease.

Interface

Interface objects are provided by DRP as an easy means for the UX and the CLI to enumerate the network interfaces on the DRP server and provide some basic information for building local subnets.

Field Definition
Name The name of the interface that the OS assigned.
Index The index of the interface. This is an OS specific index, and does not mean anything to DRP directly.
Addresses A list of CIDR addresses that are bound to the interface.
ActiveAddress The CIDR address that you should use as the Subnet address if you want to create a Subnet specifically for this interface.

DHCP Option

The DHCP Option object holds templated values for DHCP options that should be returned to clients in response to requests.

Field Definition
Code A byte that holds the numeric DHCP option code. See RFC 2132 and friends for what these codes can be.
Value A string that will be template-expanded to form a valid value to return as the DHCP option. Template expansion happens in the context of the source options.

Subnet

The subnet object defines the configuration of a single subnet for the DHCP server to process. Multiple subnets are allowed. The subnet can be attached to a local interface on DRP or relayed to DRP via a DHCP relay.

Field Definition
Name The unique name of this subnet.
Enabled A boolean value that indicates whether this subnet is available to hand out new Leases, and whether to allow renewals of any Leases in its range. Setting this to true allows the subnet to operate normally, and setting it to false will cause DRP to refuse to hand out new Leases for addresses in its range and will cause lease renewals for already existing Leases in its address range to fail.
Strategy A string that determines how the subnet will uniquely identify part of the DHCP request for address assignment.
Proxy A boolean value that indicates that DRP should respond to requests for addresses in this address range as if it was a proxy DHCP server (as defined in section 2 of the PXE specification).
Unmanaged A boolean value that indicates whether DRP will send any DHCP options required for a system to boot over the network. If this bit is set, DRP will never send any DHCP options that may be needed to network boot a system.
Subnet The network address in CIDR form of this subnet. Subnets may not have overlapping address ranges.
ActiveStart This is the start of the IP address range that this subnet will hand out. It must be within the address range the subnet is responsible for, and it must be less than ActiveEnd.
ActiveEnd This is the end of the IP address range that this subnet will hand out. It must be within the address range the subnet is responsible for, and it must be greater than ActiveStart.
ActiveLeaseTime Time in seconds that a lease created in this subnet will be valid for.
ReservedLeaseTime Time in seconds that a lease created by a reservation in this subnet will be valid for. It overrides ActiveLeaseTime.
OnlyReservations If set to true, then leases in this subnet range can only be created if there is a reservation created for the requested address.
Options A list of DhcpOption objects that should be returned in any replies to DHCP requests.

Reservation

Reservations are what the DRP DHCP service uses to ensure that an IP address is always issued to the same device.

Field Definition
Strategy The strategy that the DHCP service should use to determine whether this reservations should be used.
Token The string that the strategy uniquely identifies a network interface with.
Address The IP address that is being reserved.
Options The DHCP options that should be returned when creating or renewing a Lease based on this reservation.

Note

If you create a static reservation, DRP will always respond to the request even if the subnet is disabled.

Lease

Leases track what IP addresses the system has handed out to what strategy/token pairs.

Field Definition Value
Strategy The strategy that the DHCP service used to allocate the IP address this lease handed out.
Token The string that the strategy uniquely identifies a network interface with.
Address The IP address that was handed out.
State The state the lease is in.
PROBE The IP address is being probed via ICMP Echo Requests to make sure it is not in use by another system.
OFFER The IP address was offered to a system in response to a DHCP discover.
ACK The IP address was offered in response to a DHCP request.
ExpireTime The time at which the lease expires.