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 66
Possible 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.
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