Auto Configuration is successful when an image or configuration file is
downloaded to the switch from a TFTP server.
The downloaded configuration file is not automatically saved to startup-
config. You must explicitly issue a save request (copy running-config startup-
config) in order to save the configuration.
Obtaining IP Address Information
DHCP is enabled by default on the Out-of-Band (OOB) interface. It is
disabled by default on VLAN 1, which is the default management VLAN and
includes all switch ports as members. If an IP address has not been assigned,
the switch issues requests for an IP address assignment.
A network DHCP server returns the following information:
IP address and subnet mask to be assigned to the interface
IP address of a default gateway, if needed for IP communication
After an IP address is assigned to the switch, if a hostname is not already
assigned, Auto Configuration issues a DNS request for the corresponding
hostname. This hostname is also displayed as the CLI prompt (as in response
to the hostname command).
Obtaining Other Dynamic Information
The following information is also processed and may be returned by a
BOOTP or DHCP server:
Name of configuration file (the
67) to be downloaded from the TFTP server.
Identification of the TFTP server providing the file. The TFTP server can
be identified by name or by IP address as follows:
hostname: DHCP option 66 or the
IP address: DHCP option 150 or the
When a DHCP OFFER identifies the TFTP server more than once, the
DHCP client selects one of the options in the following order:
66, option 150,
server is required to translate the name to an IP address.
Auto Image and Configuration Update
. If the TFTP server is identified by hostname, a DNS
file field in the DHCP header or option
sname field in the DHCP header)
siaddr field in the DHCP header