Dhcp Auto Configuration - Cisco 500 series Administration Manual

Managing System Files

DHCP Auto Configuration

DHCP Auto Configuration
Cisco 500 Series Stackable Managed Switch Administration Guide
The switch supports DHCP auto configuration, which provides a means of passing
configuration information (including the IP address of a TFTP TFTP or SCP server
and a file name) to hosts on a TCP/IP network. Based on this protocol, the Auto
Configuration feature enables a switch to download configuration files from a
TFTP/SCP server.
By default, the switch is enabled as a DHCP client when the Auto Configuration
feature is enabled.
The Auto Configuration process also supports downloading a configuration file
without sensitive information, or a configuration file which includes sensitive
information, such as TACACS+ keys and SSH/SSL keys, by using the Secured
Copy Protocol (SCP).
Triggering DHCP Auto Configuration
The Auto Configuration process is triggered in the following cases:
• After reboot when an IP address is allocated or renewed dynamically (using
DHCP).
• Upon an explicit DHCP renewal request and if the switch and the server are
configured to do so.
• Upon automatic renewal of the DHCP lease.
Server Name/Address
You can specify the IP address or the name of the TFTP/SCP server. This server is
used if no server IP address was specified in the DHCP message. This DHCP
message is the DHCP offer message coming from the DHCP server. Possible
options are bootp options sname and siaddr and DHCP option 150 or option 66.
This is an optional parameter.
Backup Configuration File Name
You can specify the backup configuration filename. This file is used if no filename
was specified in the DHCP message. This is an optional parameter.
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