Users Guide

When the iDRAC or CMC obtains an IP address from the DHCP server, the XML file is used to configure the devices.
Auto-config is invoked only after the iDRAC gets its IP address from the DHCP server. If it does not get a response or an IP
address from the DHCP server, then auto-config is not invoked.
NOTE:
● You can enable Auto Config only if DHCPv4 and the Enable IPv4 options are enabled.
● Auto Config and auto-discovery features are mutually exclusive. You must disable auto-discovery for the Auto Config
feature to work.
If all the Dell PowerEdge servers in the DHCP server pool are of the same Model type and number, then a single xml file
(config.xml) is required. (This is the default XML file name.)
You can configure individual servers using different configuration files mapped using individual host names. In an environment
that has different servers with specific requirements, you can use different XML filenames to distinguish each server.
For example, if there are two servers – a PowerEdge R720 and a PowerEdge R520, you must use two XML files, R720-
config.xml and R520-config.xml.
The server-config-agent uses the rules in the following sequence to determine which XML file(s) on the File Share to apply for
each iDRAC/PowerEdge server:
1. The filename specified in DHCP option 60.
2. <ServiceTag>-config.xml - If a filename is not specified in DHCP option 60, use the system service tag to uniquely
identify the XML config file for the system. For example, <servicetag>-config.xml
3. <Model number>-config.xml - If the option 60 filename is not specified and the <ServiceTag>-config.xml
file is not found, then use the system Model number as the basis for the XML config file name to use. For example,
R520-config.xml.
4. config.xml – If the option 60 filename, service tag-based, and model number—based files are not available, use the
default config.xml file.
Related concepts
Auto Config Sequence on page 41
DHCP Options on page 41
Related tasks
Enabling Auto Config Using iDRAC Web Interface on page 43
Enabling Auto Config Using RACADM on page 44
Auto Config Sequence
1. Create or modify the XML file that configures the attributes of Dell servers.
2. Place the XML file in a share location that is accessible by the DHCP server and all the Dell servers that are assigned IP
address from the DHCP server.
3. Specify the XML file location in vendor-option 43 field of DHCP server.
4. The iDRAC as part of acquiring IP address advertises vendor class identifier iDRAC. (Option 60)
5. The DHCP server matches the vendor class to the vendor option in the dhcpd.conf file and sends the XML file location
and XML file name to the iDRAC.
6. The iDRAC processes the XML file and configures all the attributes listed in the file
DHCP Options
DHCPv4 allows a large number of globally defined parameters to be passed to the DHCP clients. Each parameter is known as
a DHCP option. Each option is identified with an option tag, which is a 1 byte value. Option tags 0 and 255 are reserved for
padding and end of options, respectively. All other values are available for defining options.
The DHCP Option 43 is used to send information from the DHCP server to the DHCP client. The option is defined as a text
string. This text string is set to contain the values of the XML filename, share location and the credentials to access the
location. For example,
option myname code 43 = text;
option myname "-l 10.35.175.88://xmlfiles –f dhcpProv.xml -u root -p calvin";
Setting Up Managed System and Management Station
41