You can follow several vSphere Auto Deploy best practices, set up networking, configure vSphere HA, and otherwise optimize your environment for vSphere Auto Deploy.
See the VMware Knowledge Base for additional best practice information.
vSphere Auto Deploy and vSphere HA Best Practices
You can improve the availability of the virtual machines running on hosts provisioned with vSphere Auto Deploy by following best practices.
Some environments configure the hosts provisioned with vSphere Auto Deploy with a distributed switch or configure virtual machines running on the hosts with Auto Start Manager. In such environments, deploy the vCenter Server system so that its availability matches the availability of the vSphere Auto Deploy server. Several approaches are possible.
- Deploy vCenter Server. The vSphere Auto Deploy server is included.
- Run vCenter Server in a vSphere HA enabled cluster and configure the virtual machine with a vSphere HA restart priority of high. Include two or more hosts in the cluster that are not managed by vSphere Auto Deploy and pin the vCenter Server virtual machine to these hosts by using a rule (vSphere HA DRS required VM to host rule). You can set up the rule and then disable DRS if you do not want to use DRS in the cluster. The greater the number of hosts that are not managed by vSphere Auto Deploy, the greater your resilience to host failures.
Note: This approach is not suitable if you use Auto Start Manager. Auto Start Manager is not supported in a cluster enabled for vSphere HA.
vSphere Auto Deploy Networking Best Practices
Prevent networking problems by following vSphere Auto Deploy networking best practices.
- vSphere Auto Deploy and IPv6
- Because vSphere Auto Deploy takes advantage of the iPXE infrastructure, if the hosts that you plan to provision with vSphere Auto Deploy are with legacy BIOS, the vSphere Auto Deploy server must have an IPv4 address. PXE booting with legacy BIOS firmware is possible only over IPv4. PXE booting with UEFI firmware is possible with either IPv4 or IPv6.
- IP Address Allocation
- Use DHCP reservations for address allocation. Fixed IP addresses are supported by the host customization mechanism, but providing input for each host is not recommended.
- VLAN Considerations
Use vSphere Auto Deploy in environments that do not use VLANs.
If you intend to use vSphere Auto Deploy in an environment that uses VLANs, make sure that the hosts that you want to provision can reach the DHCP server. How hosts are assigned to a VLAN depends on the setup at your site. The VLAN ID might be assigned by the switch or the router, or might be set in the host's BIOS or through the host profile. Contact your network administrator to determine the steps for allowing hosts to reach the DHCP server.
vSphere Auto Deploy and VMware Tools Best Practices
When you provision hosts with vSphere Auto Deploy, you can select an image profile that includes VMware Tools, or select the smaller image associated with the image profile that does not contain VMware Tools.
You can download two image profiles from the VMware download site.
- xxxxx-standard: An image profile that includes the VMware Tools binaries, required by the guest operating system running inside a virtual machine. The image is usually named esxi-version-xxxxx-standard.
- xxxxx-no-tools: An image profile that does not include the VMware Tools binaries. This image profile is usually smaller has a lower memory overhead, and boots faster in a PXE-boot environment. This image is usually named esxi-version-xxxxx-no-tools.
With vSphere 5.0 Update 1 and later, you can deploy ESXi using either image profile.
- If the network boot time is of no concern, and your environment has sufficient extra memory and storage overhead, use the image that includes VMware Tools.
- If you find the network boot time too slow when using the standard image, or if you want to save some space on the hosts, you can use the image profile that does not include VMware Tools, and place the VMware Tools binaries on shared storage. See, Provision ESXi Host by Using an Image Profile Without VMware Tools.
vSphere Auto Deploy Load Management Best Practices
Simultaneously booting large numbers of hosts places a significant load on the vSphere Auto Deploy server. Because vSphere Auto Deploy is a Web server at its core, you can use existing Web server scaling technologies to help distribute the load. For example, one or more caching reverse proxy servers can be used with vSphere Auto Deploy. The reverse proxies serve up the static files that make up the majority of an ESXi boot image. Configure the reverse proxy to cache static content and pass all requests through to the vSphere Auto Deploy server. For more information, watch the video "Using Reverse Web Proxy Servers for vSphere Auto Deploy Scalability":
Use multiple TFTP servers to point to different proxy servers. Use one TFTP server for each reverse proxy server. After that, set up the DHCP server to send different hosts to different TFTP servers.
When you boot the hosts, the DHCP server redirects them to different TFTP servers. Each TFTP server redirects hosts to a different server, either the vSphere Auto Deploy server or a reverse proxy server, significantly reducing the load on the vSphere Auto Deploy server.
After a massive power outage, bring up the hosts on a per-cluster basis. If you bring multiple clusters online simultaneously, the vSphere Auto Deploy server might experience CPU bottlenecks. All hosts might come up after a delay. The bottleneck is less severe if you set up the reverse proxy.
vSphere Auto Deploy Logging and Troubleshooting Best Practices
To resolve problems that you encounter with vSphere Auto Deploy, use the vSphere Auto Deploy logging information from the vSphere Client and set up your environment to send logging information and core dumps to remote hosts.
- vSphere Auto Deploy Logs
- Download the vSphere Auto Deploy logs by going to the vSphere Auto Deploy page in the vSphere Client. See, Download vSphere Auto Deploy Logs.
- Setting Up Syslog
- Set up a remote syslog server. See the vCenter Server and Host Management documentation for syslog server configuration information. Configure the first host you boot to use the remote syslog server and apply that host's host profile to all other target hosts. Optionally, install and use the vSphere Syslog Collector, a vCenter Server support tool that provides a unified architecture for system logging, enables network logging, and lets you combine logs from multiple hosts.
- Setting Up ESXi Dump Collector
- Hosts provisioned with vSphere Auto Deploy do not have a local disk to store core dumps on. Install ESXi Dump Collector and set up your first host so that all core dumps are directed to ESXi Dump Collector, and apply the host profile from that host to all other hosts. See Configure ESXi Dump Collector with ESXCLI.
Using vSphere Auto Deploy in a Production Environment
When you move from a proof of concept setup to a production environment, take care to make the environment resilient.