Cisco SF220-24 Administration Manual page 57

Administration: File Management
DHCP Auto Configuration
Cisco 220 Series Smart Switches Administration Guide Release 1.1.0.x
DHCP Server Options
DHCP messages may contain the configuration server name/address and the
configuration file name/path (these are optional options). These options are found
in the Offer message coming from the DHCPv4 servers and in the Information
Reply messages coming from DHCPv6 servers.
Backup information (configuration server name/address and configuration file
name/path) can be configured on the DHCP Auto Configuration page. This
information is used when the DHCPv4 or DHCPv6 message does not contain this
information.
Auto Configuration Process
When the Auto Configuration process is triggered, the following sequence of
events occurs:
• The DHCP server is accessed to acquire the TFTP server name/ address
and configuration file name/path (DHCPv4 options: 66,150, and 67, DHCPv6
options: 59 and 60).
• If a server and configuration file options are not supplied by the DHCP
server, the user-defined, backup configuration file name is used for DHCPv4
or DHCPv6.
• If the DHCP server does not send these options and the backup TFTP
server address parameter is empty, then the switch sends TFTP request
messages to limited Broadcast IPv4 address and continues the process of
Auto Configuration with the first answering TFTP server.
Configuring DHCP Auto Configuration Parameters
To configure DHCP Auto Configuration, you need to perform the following:
• Configure the DHCPv4 and/or DHCPv6 servers to send the required
options. This process is not described in this guide.
• Configure the DHCP Auto Configuration parameters as described in this
section.
• Set the IP Address Type to Dynamic on the IPv4 Interface page, as
described in the
Use the DHCP Auto Configuration page to perform the following actions when the
information is not provided in a DHCP message:
• Enable the DHCP Auto Configuration feature.
IPv4 Management and Interface
4
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