VMware configuration: Verifying and viewing VMware ESX Server configuration files

Before starting a VMware configuration, follow these best practices for preparing a VMware ESX Server configuration from Virtualization: From the Desktop to the Enterprise.

IT reseller takeaway: Before you attempt a VMware configuration, make sure VMware ESX Server is ready to communicate on your clients' networks. This book excerpt from Virtualization: From the Desktop to the Enterprise offers best practices for verifying and viewing ESX Server files.

Verifying ESX Server Configuration Information

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When ESX Server is booting, you can get a good idea of what services are being loaded. If you've used Linux-type operating systems, you'll encounter a familiar boot process. Before you start the configuration of ESX Server, let's make sure the system is ready to communicate on the network. For Unix and Linux users, this section will seem basic, but it's essential for Microsoft administrators. If you're familiar with the information, skim this section and use it as a review.

You'll want to check the server's basic configuration, so you'll need to gain shell access by pressing Ctrl+Alt+F2. You can switch between shell sessions by pressing Ctrl+Alt+F1 through F12. So you can get an idea of how it works, toggle between the Welcome screen and the shell Login screen.

At the shell Login screen, enter the administrator's username root, and use the password you configured earlier for the account.

Caution: Unlike Microsoft OSs that are generally case insensitive, every command in Linux-like operating systems is CaSe sEnsiTive. Everything! For instance, ROOT isn't the same thing as Root or root. These are all three different user accounts, and only one is the superuser administrator account—root.

After logging into the ESX Server CLI, the first thing you'll want to check is the system's IP address information. Type ifconfig | less at the command line. (You could use the pipe with the more command, but less allows scrolling up and down with the arrow keys. Type q to quit.) You should have information for the loopback address (lo) and a minimum of two Ethernet controllers (eth0 and eth1). Remember that you need at least two NICs to bridge or NAT VMs to your network. If you dedicate a single NIC to VMs, you'll lose the ability to connect to the Service Console with a Web browser.

Confirm that your server's information is correct, and then test the following using the ping command. You can use Ctrl+C to break out of the looping echo requests and echo replies.

  • Test the server's TCP/IP stack by pinging the loopback address with ping
  • Test the server's default gateway with ping .
  • Test DNS by pinging a Web site with ping www.apress.com, for example. Some Web servers block ICMP traffic, so you may get only the domain name to resolve to an IP address.

Viewing configuration files

If you have a problem with the ping tests listed previously, you'll have a problem configuring ESX Server through a Web browser. If no IP address information exists, you can attempt to use the setup command to configure your IP address information. A better solution to verifying configuration information is to check the configuration files from the command line. Though we could easily turn this into a Linux tutorial, we'll just walk you through the basics.

Editing configuration files starts with a good text editor and enough knowledge to be dangerous, so now is as good a time as any to discuss the Vi editor: some of us hate it, and some of us love it. It comes with nearly every version of Linux; you can even find it in the Microsoft NT Resource Kit. Whether you're a fan of Vi or not, it's an excellent text editor that gets the job done. Table 5-3 lists the commands you'll need to memorize for ESX Server administration.

Table 5-3. Vi Survival Commands

Command Action
vi Starts the Vi editor
vi <filename> Starts Vi and opens the given file for editing
:q! Exits the Vi editor without saving changes (quit!)
:wq! Exits the Vi editor and saves changes (write and quit!)
:set nu Turns on line numbering
esc Exits text insert mode
i Enters text insert mode
Arrow keys Navigates the cursor
Backspace key Deletes previous character
Delete Deletes selected character

Vi has two different running modes: command mode and edit mode. In command mode, every keystroke is interpreted as a command and performs file functions such as editing and saving. These commands are referred to as colon commands because they start with a colon. You know you're in command mode because you won't see "INSERT" in the lower-left corner of your display. The lower-left corner should display a colon when executing colon commands. If you have any doubts as to what mode you're in, press the Escape key (several times) to enter command mode.

In text mode, typed characters are echoed to the screen and temporarily become part of the open document. Enter text mode from command mode by typing a lowercase i (for insert mode). Use the arrow keys to navigate the cursor, and use the Backspace and Delete keys to remove characters. To quit without saving your current work, or to save your current work and quit, refer to Table 5-3.

Now that Text Editing 101 is out of the way, you can verify your ESX Server configuration information using the filenames listed next. For each file, open and view your system's information. If anything is incorrect, take a moment to fix any errors and save your changes.

You can find configuration files relating to the host name (FQDN) of your system in three places:

  • vi /etc/sysconfig/network
  • vi /etc/hosts
  • vi /usr/lib/vmware-mui/apache/conf/httpd.conf

IP address configuration information for the first network adapter is located in /etc/sysconfig/network-scripts/ifcfg-eth0.

The contents of the ifcfg-eth0 file will look similar to the following:


IP address information for the second network adapter is located in /etc/sysconfig/ network-scripts/ifcfg-eth1.

The contents of the ifcfg-eth1 file will look similar to the following:


You can find DNS server configuration information in the resolv.conf file. Review the contents of it by executing the following command:

vi /etc/resolv.conf

Default gateway information is located in the network file. Make sure the default gateway is properly set. If not, you'll spend needless time troubleshooting your host. Verify your host's settings with the following:

vi /etc/sysconfig/network

After verifying and making any necessary changes, restart the networking service by entering the following command:

service network restart

Continuing at the CLI, execute hostname (for example, hostname www.apress.com) to make the host name change effective without a reboot.

Next, repeat the ping tests, and verify your system's host name with uname –a.

With positive results from network connectivity and name resolution testing, the ESX Server installation is complete. You can move onto your post-installation housekeeping. You'll perform these tasks by configuring and using the MUI.


  • Introduction: Installing and deploying VMs on enterprise servers
  • Installing Microsoft Virtual Server
  • Installing VMware GSX Server for Windows
  • Installing VMware GSX Server for Linux
  • Installing the VMware management interface
  • Working with the VMware virtual machine console
  • Changing GSX Server's remote console port number
  • Installing VMware ESX Server
  • Verifiying and viewing configuration files
  • Using Linux survival commands
  • Understanding MUI and SSL
  • Configuring the ESX Server installation: Troubleshooting an ESX Server installation
  • Configuring the ESX Server installation: A smooth ESX Server installation
About the author   
Chris Wolf is an instructor at ECPI Technical College, as well as a leading industry consultant in enterprise storage, virtualization solutions, and network infrastructure management. He has a master's degree in information technology from Rochester Institute of Technology, and his IT certification list includes MCSE, MCT, and CCNA. Wolf authored MCSE Supporting and Maintaining NT Server 4.0 Exam Cram, Windows 2000 Enterprise Storage Solutions and Troubleshooting Microsoft Technologies, and he contributes frequently to Redmond Magazine and Windows IT Pro Magazine. Wolf also speaks at computer conferences across the nation.


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