Dell PowerConnect M6220, User Configuration Manual

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Auto Image and Configuration Update
Obtaining the Configuration File
If the DHCP OFFER identifies a configuration file, either as option 67 or in
the
file
field of the DHCP header, the switch attempts to download the
configuration file.
The TFTP client makes three unicast requests. If the unicast attempts fail, or
if the DHCP OFFER did not specify a TFTP server address, the TFTP client
makes three broadcast requests.
If the DHCP server does not specify a configuration file or download of the
configuration file fails, the Auto Configuration process attempts to download
a configuration file with the name
dell-net.cfg
. The switch unicasts or
broadcasts TFTP requests for a network configuration file in the same
manner as it attempts to download a host-specific configuration file.
The default network configuration file consists of a set of IP address-to-
hostname mappings, using the command ip host hostname
address
. The
switch finds its own IP address, as learned from the DHCP server, in the
configuration file and extracts its hostname from the matching command. If
the default network configuration file does not contain the switch's IP
address, the switch attempts a reverse DNS lookup to resolve its hostname.
A sample
dell-net.cfg
file follows:
config
...
ip host switch1 192.168.1.10
ip host switch2 192.168.1.11
... <other hostname definitions>
exit
Once a hostname has been determined, the switch issues a TFTP request for
a file named
hostname .cfg
, where
hostname
is the first thirty-two
characters of the switch's hostname.
If the switch is unable to map its IP address to a hostname, Auto
Configuration sends TFTP requests for the default configuration file
host.cfg.
NOTE:
The configuration file is required to have a file type of *.cfg.