Mastering VMware® Infrastructure3

ESXi can be managed in several ways, including from the local console, VirtualCenter, VI Client, or a remote command-line interface. VirtualCenter will be the most common choice in order to have the opportunity to manage a mixture of ESX Server 3.5 versions within the same VirtualCenter.

ESXi Console

Once the ESXi installation is complete or if your new ESXi Embedded server has just arrived, you can use the local console to perform some limited configuration of the host. Each of the following sections details the ESXi management tasks available from the console.

By pressing the F2 key, you'll be offered the Customize System screen where configuration takes place. The first option in the list is the Configure Root Password option, shown in Figure 13.8. Pressing the Enter key will open the Configure Root Password box, shown in Figure 13.9.

Figure 13.8 ESXi provides a simple-to-use interface for customizing the installation.

Figure 13.9 Change the root password upon first boot of the ESXi thin hyper-

ESXi includes a configuration option that allows administrators to prevent direct access to an ESXi host via the VI Client application under the context of the root user. Access directly to the system using the VI Client is still permissible with nonroot user accounts. If no other accounts except the root exist, then the only way to manage the server would be remotely from VirtualCenter or the Remote Command-Line Interface (RCLI). Figures 13.10 and 13.11 show the Configure Lockdown Mode option and the enabling of the option.

Figure 13.10 Lockdown mode prevents root user access to the system via the VI Client.

Figure 13.11 Lockdown mode can be enabled and disabled as needed to support server management.

Selecting the Configure Network Management option, shown in Figure 13.12, offers a set of options for configuring network communications like physical NIC assignment, IP address, subnet mask, DNS, and so forth.

Figure 13.12 The network communication parameters of an ESXi host can be altered as part of the post-installation configuration.

The Configure Network Management option provides a submenu for each of the following:

Network Adapters As shown in Figure 13.13, the Network Adapters screen allows you to select which network adapter in the computer should be used for host management. Multiple adapters can be selected for providing redundancy and load balancing to the host management traffic.

Figure 13.13 One or more network adapters can be selected for the host's default management network.

VLAN As shown in Figure 13.14, VLAN configuration is possible on ESXi. VLANs are used to segment off the management traffic when a single physical network is used for multiple data transmission types. The configuration window accepts VLAN IDs in the range of 1 to 4094, or use 4095 for access to all VLANs.

Figure 13.14 VLANs can provide traffic segmentation for the host's management network.

IP Configuration As shown in Figure 13.15, IP Configuration allows for the configuration of a static IP address, a subnet mask, and a default gateway. The default is for the host to obtain an IP address via DHCP. It is always best to provide enterprise servers, especially ESX Server hosts, with a static IP address.

DNS Configuration As shown in Figure 13.16, DNS Configuration allows for the configuration of primary and alternate DNS servers as well as the hostname for the ESXi host. As with ESX Server 3.5, hostname resolution is an important part of the host's functionality. Therefore, a corresponding Host (A) record should be created in DNS with the name of each ESXi host referencing the IP address as assigned in the IP Configuration page.

Figure 13.15 ESXi hosts can be configured with static IP address information or remain set to the default of obtaining an IP address from DHCP.

Figure 13.16 ESXi hosts can be configured with multiple DNS servers and a unique hostname to be referenced by other servers in the VirtualCenter inventory.

Custom DNS Suffixes As shown in Figure 13.17, Custom DNS Suffixes allows for the configuration of DNS suffixes that are appended when a host uses short, unqualified names. Multiple suffixes can be listed by separating each suffix with a space. For example, if the DNS suffixes include vdc.local, learn.vmw, and vdc.vmw, and the host references the unqualified name of Silo108, the suffixes will be appended until a name can be resolved. The first name tried will be silo108.vdc.local, followed by silo108.learn.vmw if no response is returned from the first suffix attempt, followed by silo108.vdc.vmw if no response is returned from either of the first two suffix attempts.

Figure 13.17 DNS suffixes allow hosts to reference other systems using short, unqualified names.

The option to restart the management network forces a DHCP lease renewal. If the ESXi host is configured to obtain an IP address via DHCP, this option could force a change in the IP address, resulting in loss of access to the host because the DNS entry for the host would retain the old IP address configuration. For this reason alone, it is a good idea, and strongly suggested, that ESX Server hosts be manually configured with static IP address information. Since ESX Servers do not perform a dynamic update of DNS records, administrators will need to carefully manage the Host (A) records of each ESX Server to ensure they are accurate in the event of an IP address change.

The Test Management Network option in the Customize System menu list is an excellent troubleshooting utility. It can be used to test IP connectivity and name resolution. The option uses the ping utility against the default gateway, the primary DNS server, and the alternate DNS server. In addition, it will attempt to resolve your hostname. Figures 13.18 and 13.19 show the test configuration and the test operation.

Figure 13.18 ESXi has a built-in utility for troubleshooting IP connectivity and name resolution.

Figure 13.19 Using the Test Management Network can be extremely helpful in determining if problems stem from host configuration issues or external configuration issues.

This tool will be helpful when you are having problems connecting to an ESXi host, as it allows you to rule out internal configuration issues. As you have probably seen, the configuration of ESXi is minimal already, so this tool will help you identify local versus external configuration issues. In the case when all tests came back with an OK status, it would be more likely that any type of connectivity problem is coming from an external configuration problem, not a problem with the ESXi host upon which this test was performed. The test results identify that IP connectivity is good, the DNS server is responding, and that name resolution for the local host hostname is working.

As the name suggests, this option allows for the configuration of the keyboard. The options include:

♦ Default

♦ French

♦ German

♦ Japanese

♦ Russian

The View Support Information option provides information about:

♦ Serial number

♦ License serial number

♦ SSL Thumbprint (SHA1)

The View System Logs option provides a look at several logs, including:

♦ Messages (press 1)

♦ Config (press 2)

♦ Management agent (hostd) (press 3)

♦ VirtualCenter agent (vpxa) (press 4)

Once you have selected a particular log to view, press the H key to get help on how to navigate through the logs. As shown in Figure 13.20, the logs (hostd is shown) are plain text and human-readable logs but certainly require some experience in going through them. The value in these logs is in knowing how to get to them and how to navigate them to troubleshoot when problems arise. It is unlikely that you will regularly visit these logs on a voluntary basis.

This option, as the name suggests, allows for restarting the management agents (hostd) that govern the remote management and control of the ESXi thin hypervisor. Executing a restart of hostd will cause a temporary loss of access to the hypervisor.

This option reverts back to all defaults that exist just after the installation of ESXi. This includes resetting IP configuration and the root password and the unregistering of virtual machines.

Figure 13.20 Logs on ESXi are accessible and can be reviewed for troubleshooting or maintenance.

VI Client

Once your initial configuration from the console is completed, your management tasks will shift to using the more user-friendly VI Client. The VI Client can be used to connect directly to an ESXi host, as shown in Figure 13.21, but the more common method will be to connect through VirtualCenter (coming up next).

Figure 13.21 The VI Client can be used to connect directly to an ESXi host.

Notice in Figure 13.21 that the host is presented with a configuration issue stating that the ESX Server does not have persistent storage. If a server is set up to run the ESXi Embedded version but still contains local hard drives, remember that the local drives are not used during the installation procedure and remain empty. The server in Figure 13.21 is running ESXi Embedded. In Figure 13.22, the VI Client is connected to a server running ESXi Installable and does not show that error. You can see in the figure that a local storage device is configured. Remember in the previous section, on deploying ESXi Installable, that the installation process required the selection of a hard disk. Therefore, a storage device is already configured.

Figure 13.22 ESXi Installable hosts have storage devices configured as part of the installation process.

VirtualCenter 2.5

As noted in the previous section, VI Client connections to VirtualCenter will be the most common means of managing an ESXi host. All in all, your management of an ESXi host should be no different than the management of an ESX Server 3.5 host. The architectures may differ, but together in the same datacenters and clusters they will act no differently. Figure 13.23 displays the Hosts tab of a datacenter in the VirtualCenter inventory. With the exception of the naming scheme, it is not possible to tell which server is running the ESXi product as opposed to ESX Server 3.5.

One distinct difference that can be seen when managing an ESXi host is the existence of the Health Status option from the Hardware menu on the Configuration tab. Figure 13.24 shows the hardware monitoring data that is discovered as part of the health status of an ESXi host.

Once added to a VirtualCenter inventory, an ESXi host is capable of all the same enterprise features of VMotion, DRS, and HA. These thin hypervisor hosts are susceptible to all the feature constraints as any other host. Networking requirements, storage requirements, and so forth must all be met to support these features.

Figure 13.23 ESXi hosts are managed right alongside the ESX Server 3.5 hosts in VirtualCenter.

Figure 13.24 ESXi hosts have an additional menu item for monitoring the hardware health status.

Remote Command-Line Interface (RCLI)

With no console operating system to connect to, ESXi would seem to be limited in its management capability. However, for those environments with many servers whose administrators refuse to perform tasks repeatedly through the VI Client, VMware now provides a remote command-line interface for host management. This tool is available in two formats:

♦ Remote CLI installable package for installation on Windows or Linux

♦ Remote CLI virtual machine appliance

Both tools can be downloaded from the VMware website. The Remote CLIs support a long list of commands for managing ESX Server hosts. The tools are based on the VMware Infrastructure (VI) Perl Toolkit, which relies on Perl and a few other libraries.

For each of the remote CLI commands, the following options are available as part of the command execution:

--config Specifies the location of the configuration to be used, which must be a location accessible from the current directory. The equivalent variable used in a configuration file is VICONFIG.

--password Specifies the password for use in combination with the --username parameter. If the username and password are not specified in the execution string, you will be prompted for them. The equivalent variable used in a configuration file is VI PASSWORD.

--portnumber Used to specify the port used to connect to the ESX Server host. The default port is 443. The equivalent variable used in a configuration file is VIPORTNUMBER.

--protocol Used to specify the protocol used to connect to the ESX Server host. The default protocol is HTTPS. The equivalent variable used in a configuration file is VIPROTOCOL.

--server Used to identify the server against which the command should be run. The default is the localhost. The equivalent variable used in a configuration file is VISERVER.

--servicepath Used to identify the service path to connect to the ESX Server host. The default is /sdk/webService. The equivalent variable used in a configuration file is VISERVICEPATH.

--sessionfile Used to reference a saved session file. The equivalent variable used in a configuration file is VISESSIONFILE.

--url Used to connect to the VI SDK specified in the URL. The equivalent variable used in a configuration file is VIURL.

--username Used to specify the username for the authentication context. If the username and password are not specified, you will be prompted for them. The equivalent variable used in a configuration file is VIUSERNAME.

--verbose Used to provide more detail in the debugging information. The equivalent variable used in a configuration file is VIVERBOSE.

--version Used to display version information.

Here is a list of commands with explanations and samples:

resxtop This command provides real-time monitoring of ESX CPU, memory, disk, and network adapter utilization. To run resxtop on an ESX host with an IP address of 172.30.0.105, use the following command:

resxtop -server 172.30.0.105 -username root

Once the tool is running, use the C, M, D, and N keys to switch between CPU, memory, disk, and network counters, respectively. Figures 13.25 and 13.26 show the resxtop output for CPU and memory.

Figure 13.25 The resxtop Remote CLI command provides CPU utilization data.

svmotion This command performs the storage migration process of moving the disk files of a virtual machine to a different LUN.

vicfg-advcfg This option is not recommended for customer use. This command is typically used only under the guidance of VMware technical support.

Figure 13.26 Pressing the M key makes resxtop display data regarding memory utilization.

vicfg-cfgbackup This tool allows for the backup and restore of the configuration data of an ESXi host.

vicfg-dumppart This tool allows for querying, setting, and scanning the diagnostic data "dumps" of an ESX Server host.

vicfg-mpath This tool allows for the configuration of multipathing settings for fibre channel or iSCSI LUNs.

vicfg-nas This tool provides settings and parameters for managing NFS access for your ESX Server host. For example, the following syntax adds a NAS datastore named NFSDS to a server named silo107.vdc.local. The NFS server is named nfs1.vdc.local and has a directory named /iso that is shared:

vicfg-nas --server silo107.vdc.local --username root --password -a -o nfs1.vdc.local -s /iso NFSDS

vicfg-nics This tool provides management of physical network adapters. Figure 13.27 shows a simple listing of all network adapters on a server with an IP address of 172.30.01 using the following syntax:

vicfg-nics --server 172.30.0.105 --username root --list

Figure 13.27 The vicfg-nics tool can identify details about network adapters.

vicfg-ntp This command allows for the configuration of NTP servers for the 3i hosts.

vicfg-rescan This command executes a remote HBA rescan.

vicfg-route This command allows for setting the IP address of the default gateway for the VMkernel.

vicfg-snmp This command allows for the configuration of SNMP for ESX Server hosts.

vicfg-syslog This command allows for the specification of the remote syslog server for an ESX Server host.

vicfg-vmhbadevs This command provides information regarding the LUNs available to an ESX Server host.

vicfg-vmknic This command allows for the configuration of VMkernel network adapters.

vicfg-vswitch This command allows for adding, removing, and modifying virtual switches and virtual switch properties. Review the following examples. Keep in mind that the parameters of --server and --username (and then a password) would be required to run the commands against a remote host.

To add a new virtual switch named vSwitch3:

vicfg-vswitch --add vSwitch3

To add a new port group named TestVMs to vSwitch3:

vicfg-vswitch --add-pg="TestVMs" vSwitch3

To list all the virtual switches:

vicfg-vswitch -l

vihostupdate This command allows for the management of software updates on an ESXi host. It provides the necessary parameters for applying software updates and monitoring installed updates.

vifs This command allows copying, removing, getting, and putting on files and directories.

vmkfstools This command allows for the creation and manipulation of file systems (VMFS), virtual disks (VMDK), logical volumes, and physical storage devices.

All of these commands can be combined with the use of a configuration file to simplify the scripting syntax. A configuration file is a file accessible by the system where the remote command line is being generated (Windows host, Linux host, or virtual appliance) that allows for commonly used parameters to be stored in a file and then referenced as part of the CLI command execution. A configuration file for a host named silo101.vdc.local would include information as shown here:

VI_SERVER=silo101.vdc.local

VI_USERNAME= root

VI_PASSWORD = learnvmware

This configuration file is then called in during the execution of the command as shown in the following syntax. This command would create an NFS datastore named NFS ISOs on the host silo101.vdc.local that points to an /iso directory on an NFS server named nfsserver.learn.vmw:

vicfg-nas --config  -a -o nfsserver.learn.vmw -s /iso NFS_ISOs