You can configure the integrated Dell Remote Access Controller (iDRAC) at server boot time by pressing [CTRL]+[E].  There is also the option to install Dell OpenManage Server Administrator (OMSA) or the ‘Racadm’ utility from inside the operating system.  Using either one of these enables you to interface with the system (and read/write the iDRAC configuration).  OMSA offers both a user interface (web page) and a command line interface where the Racadm utility offers only a command line interface.  Using a Remote Desktop Protocol (RDP) connection (mstsc.exe) you can use any of these tools remotely if need be.

Web Interface (OMSA)

Web interface: OpenManage | Main Chassis | Remote Access | Configuration tab | Scroll down to IPv4 fields.

Command Line Interface

Racadm utility

You can type RACADM commands locally or remotely. When using RACADM commands remotely, you must include user name, password, and IP address. 

> racadm getsysinfo
> racadm -r <ip_address> -u <username> -p <password> getsysinfo

To type RACADM commands locally, use the following syntax from a command prompt on the managed system:

  To read:  racadm getconfig -g <group -o <property>
  To write: racadm config -g <group> -o <property> <value>

To view the list of groups:

> racadm getconfig -h

To view a list of properties:

> racadm getconfig -g <group>

To view the basic iDRAC configuration:

> racadm getconfig -g idRacInfo

idRacType=16
idRacProductInfo=Integrated Dell Remote Access Controller
idRacDescriptionInfo=This system component provides a complete set of remote management functions for Dell PowerEdge Servers
idRacVersionInfo=1.40.40
idRacBuildInfo=17
idRacName=idrac

> omreport about
Product name : Dell OpenManage Server Administrator
Version      : 7.3.0-1
Copyright    : Copyright (C) Dell Inc. 1995-2013 All rights reserved.
Company      : Dell Inc.

> omreport chassis remoteaccess config=user
(iDRACv7 has room for up to 16 users)

The factory default is for one user to be set up with username 'root' and password 'calvin' at index 2.
(In DRAC v5+, index 1 is administrator, index 2 is root)

> racadm getconfig -g cfgUserAdmin -i 2
cfgUserAdminUserName=root
# cfgUserAdminPassword=******** (Write-Only)
cfgUserAdminEnable=1
cfgUserAdminPrivilege=0x000001ff
cfgUserAdminIpmiLanPrivilege=4
cfgUserAdminIpmiSerialPrivilege=4
cfgUserAdminSolEnable=1

> racadm config -g cfgUserAdmin -o cfgUserAdminUserName -i 2 <newusername>
> racadm config -g cfgUserAdmin -o cfgUserAdminPassword -i 2 <newpassword>
Optional:
> racadm config -g cfgUserAdmin -o cfgUserAdminEmailAddress -i 2 "user@domain.com"
> racadm config -g cfgUserAdmin -o cfgUserAdminEmailCustomMsg -i 2 “Your description here”
> racadm config -g cfgUserAdmin -o cfgUserAdminEmailEnable -i 2 1
> racadm config -g cfgUserAdmin -o cfgUserAdminAlertFilterRacEventMask -i 2 0x0
> racadm config -g cfgUserAdmin -o cfgUserAdminAlertFilterSysEventMask -i 2 0x0
> racadm config -g cfgTraps -o cfgTrapsSnmpCommunity -i 2 public
> racadm config -g cfgTraps -o cfgTrapsEnable -i 2 1
> racadm config -g cfgTraps -o cfgTrapsFilterRacEventMask -i 2 0x0
> racadm config -g cfgTraps -o cfgTrapsFilterSysEventMask -i 2 0x0
> racadm config -g cfgTraps -o cfgTrapsDestIpAddr -i 2
> racadm config -g cfgOobSnmp -o cfgOobSnmpTrapsEnable 1
> racadm config -g cfgRemoteHosts -o cfgRhostsSmtpServerIpAddr <IP_address>
> racadm racreset

To generate a list of available network properties, type the following:

> racadm getconfig -g cfgLanNetworking

To use DHCP to obtain an IP address, use the following command to write the object cfgNicUseDhcp and enable this feature:

> racadm config -g cfgLanNetworking -o cfgNicUseDHCP 1

To configure desired iDRAC network properties:

> racadm config -g cfgLanNetworking -o cfgNicEnable 1
> racadm config -g cfgLanNetworking -o cfgNicIpAddress x.x.x.x
> racadm config -g cfgLanNetworking -o cfgNicNetmask x.x.x.x
> racadm config -g cfgLanNetworking -o cfgNicGateway x.x.x.x
> racadm config -g cfgLanNetworking -o cfgNicUseDHCP 0
Optional:
> racadm config -g cfgLanNetworking -o cfgDNSServersFromDHCP 0
> racadm config -g cfgLanNetworking -o cfgDNSServer1 x.x.x.x
> racadm config -g cfgLanNetworking -o cfgDNSServer2 x.x.x.x
> racadm config -g cfgLanNetworking -o cfgDNSRegisterRac 1
> racadm config -g cfgLanNetworking -o cfgDNSRacName <alias>
> racadm config -g cfgLanNetworking -o cfgDNSDomainNameFromDHCP 0
> racadm config -g cfgLanNetworking -o cfgDNSDomainName <domain>
> racadm racreset

OMSA (iDRAC v5=+)

> omreport chassis remoteaccess config=user
> omconfig chassis remoteaccess config=user id=<userid> dracusergroup=admin
> omconfig chassis remoteaccess config=user id=<userid> name=<username>
> omconfig chassis remoteaccess config=user id=<userid> newpw=<password> confirmnewpw=<password>
> omconfig chassis remoteaccess config=user id=<userid> enable=true
> omreport chassis remoteaccess config=user id=<userid>

> omreport chassis remoteaccess config=nic
> omconfig chassis remoteaccess config=nic ipsource=static
> omconfig chassis remoteaccess config=nic IP address=x.x.x.x
> omconfig chassis remoteaccess config=nic subnet=x.x.x.x
> omconfig chassis remoteaccess config=nic gateway=x.x.x.x
> omreport chassis remoteaccess config=nic

OMSA (iDRAC v5-)

> omconfig rac network dhcpenable=false
> omconfig rac network ipaddr=x.x.x.x
> omconfig rac network subnetmask=x.x.x.x
> omconfig rac network gateway=x.x.x.x
> omconfig rac users username=[username]
> omconfig rac users userpassword=[password]
> omconfig rac reset

The above iDRAC v5- commands will set a static IP address and adds a user to the next available free user slot in the configuration.