Switch Memory and Configuration

Automatic Configuration Update with DHCP Option 66

CLI Command

The command to enable the configuration update using Option 66 is:

Syntax: [no] dhcp config-file-update

Enables configuration file update using Option 66.

Default: Enabled

ProCurve(config)# dhcp config-file-update

Figure 6-21. Example of Enabling Configuration File Update Using Option 66Possible Scenarios for Updating the Configuration File

The following table shows various network configurations and how Option 66 is handled.

Scenario

Behavior

 

 

Single Server serving Multiple VLANs

• Each DHCP-enabled VLAN interface initiates DHCPDISCOVER

 

message, receives DHCPOFFER from the server, and send

 

DHCPREQUEST to obtain the offered parameters.

 

• If multiple interfaces send DHCPREQUESTs, it’s possible that more

 

than one DHCPACK is returned with a valid Option 66.

 

• Evaluating and updating the configuration file occurs only on the

 

primary VLAN.

 

• Option 66 is ignored by any interfaces not belonging to the primary

 

VLAN.

 

 

Multiple Servers serving a Single VLAN

• Each DHCP-enabled VLAN interface initiates one DHCPDISCOVER

 

and receives one or more DHCPOFFER messages.

 

• Each interface accepts the best offer.

 

• Option 66 is processed only for the interface belonging to the primary

 

VLAN.

6-38