DHCP Lease Query Command

Table Of Contents

DHCP Lease Query Command

Contents

Prerequisites

Command Reference

ip dhcp-server query lease

DHCP Lease Query Command

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A Cisco IOS Dynamic Host Configuration Protocol (DHCP) API was developed to query a DHCP server for information on DHCP address leases. This API implements the client side of the DHCP Lease Query protocol. The DHCP Lease Query protocol is a lightweight mechanism to query a DHCP server for certain information related to IP addresses leased from the DHCP server. Other applications, like SSG, can call the API and obtain needed information.

Feature History for DHCP Lease Query Command

Release	Modification
12.2(27)SBA	This command was introduced.

Finding Support Information for Platforms and Cisco IOS Software Images

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Contents

•Prerequisites

•Command Reference

Prerequisites

Non-DHCP component configuration may be necessary to activate the lease query used by these components. You can specify which DHCP servers to query by using the ip dhcp-server global configuration command. You can specify up to 10 servers on the network. Use the ip dhcp-server query lease global configuration command to change the default global retransmission scheme for lease query packets.

Command Reference

This section documents a new command.

•ip dhcp-server query lease

ip dhcp-server query lease

To change the default global retransmission scheme for Dynamic Host Configuration Protocol (DHCP) lease query packets, use the ip dhcp-server query lease command in global configuration mode. To remove this retransmission scheme and return to the default behavior, use the no form of this command.

ip dhcp-server query lease [retries number] [timeout seconds]

no ip dhcp-server query lease [retries number] [timeout seconds]

Syntax Description

retries number	The number of times the DHCP lease is transmitted following a timeout for an authoritative reply. The range is from 0 to 5. The default is 2 retries. A value of 0 means no retransmission (a single failure).
timeout seconds	The number of seconds to wait for a reply to a query. The range is from 1 to 60 seconds. The default is 5 seconds

Defaults

retries number : 2
timeout seconds : 5

Command Modes

Global configuration

Command History

Release	Modification
12.2(27)SBA	This command was introduced.

Usage Guidelines

The DHCP Lease Query protocol is a lightweight mechanism to query a DHCP server for certain information related to IP addresses leased from the DHCP server.

You can specify which DHCP servers to query by using the ip dhcp-server global configuration command. You can specify up to 10 servers on the network. Use the ip dhcp-server query lease global configuration command to change the default global retransmission scheme for lease query packets.

Examples

In the following example, the time to wait for a reply to a lease query is set to 15 seconds:

ip dhcp-server query lease timeout 15

In the following example, the retry number is set to 0, which means that only a single DHCP lease query will be transmitted for each DHCP server; no retries will be attempted.

ip dhcp-server query lease retries 0

Related Commands

Command	Description
ip dhcp-server	Specifies which DHCP server to use on your network.

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