«If you have an existing VI3 environment, at some point you’ll probably want to upgrade it to vSphere. Before jumping right into the upgrade process, ...»
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ROLLING BACK TO PREVIOUS VERSIONSIt is possible, but not easy, to roll back to previous versions once you have upgraded them. Therefore, before you upgrade a host, vCenter Server, or VM, be absolutely sure you are ready to do it.
Rolling Back vCenter Server For vCenter Server, it is critical to back up the SQL database before you upgrade; otherwise, once you upgrade it, you cannot go back to the old database schema. Here are the steps for rolling back vCenter Server to a previous version.
1. Completely uninstall vCenter Server 4.0.
2. Restore the vCenter Server 2.x SQL database.
3. Install vCenter Server 2.x and tell it to use an existing database, and select your restored 2.x SQL database.
4. Reconfigure your license server with your 3.x license files.
Rolling back to a previous ESX version can be tricky, but it is possible. In most cases, it is easier to just reinstall ESX 3.x. Otherwise, if you want to roll back, here are the steps.
1. In the ESX Service Console, run the /usr/sbin/rollback–to–esx3 command which reconfigures the bootloader to boot the previous ESX 3.x version. The –f parameter forces the rollback and suppresses the confirmation message. Once you run the command, you can no longer boot to ESX 4.0.
2. Reboot the host and it will boot to ESX 3.x.
3. Once the host boots to ESX 3.x, delete the ESX 4.0 Service Console VM folder (esxconsole–UUID) from the VMFS datastore.
1. Reboot the ESXi 4.0 host.
2. When you see the page that displays the current boot build, press Shift-r to select the standby build.
3. Press Shift-y to confirm the selection, and press Enter.
Rolling Back VMs For VMs, if you upgrade their virtual hardware from version 4 that is used by VI3 to version 7 that is used by vSphere, be aware that this is irreversible. If you snapshot the VM before upgrading it, it is possible to roll back if you revert to the snapshot. There is also a workaround to go back to version 4 using vCenter Converter, as outlined in the following steps.
1. Install vCenter Converter on a workstation and run it.
2. Run the Convert Machine Wizard. For the source, specify a VM type and a vCenter Server/host to connect to on which the VM is located.
3. For the destination type, select a VM and choose the same vCenter Server/host.
4. On the Host/Resource page, give the VM a different name and choose the VM hardware 4 version.
5. Once the process completes, power on the new VM, verify that it works, and then delete the original VM. Once you delete the original VM, rename the new VM to the original VM’s name.
PRE-UPGRADE CHECKLISTBefore you upgrade any part of your virtual environment there is a pre-upgrade checklist that you should use to ensure that you are ready and have covered all your bases. VMware has published the complete checklist on its website (www.vmware.com/files/pdf/vsphere-migration-prerequisites-checklist.pdf), but here are some of the most important items.
Be sure all your other VMware products and third-party products are comG patible with the vSphere version that you are installing.
Be sure all your server hardware, I/O devices, and storage devices are listed G in the Hardware Compatibility Guide for the version of vSphere that you are installing.
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vCenter database, templates in the vCenter repository, license files, and SSL certificate files before the install or upgrade.
For ESX hosts, if you are using any hardware management agents inside G the Service Console, make sure you upgrade to the latest version. Also ensure that any third-party agents, scripts, or software is upgraded to the latest version.
Tools to mount the virtual ISO and install/upgrade VMware Tools.
Ensure that it is okay to upgrade the VM hardware from version 4 to verG sion 7. Once upgraded, you cannot revert back to an earlier VM format unless you have created a snapshot of the VM prior to the changes.
Ensure that the VMs are backed up before upgrading them.
Ensure that you have the necessary licenses for the required features of G VMware vSphere. The evaluation license is valid for 60 days after you power on the ESX/ESXi host.
Ensure that you have a backup copy of the existing VI3 License Server G
Once you are sure you meet all the necessary prerequisites, you’re ready to begin upgrading your environment.
PHASE 1: UPGRADING VCENTER SERVERBefore you upgrade vCenter Server, you need to make sure you have a good backup of the SQL database and that the SQL database you are using is supported by vCenter Server 4.0. Also make sure you have downloaded the vCenter Server installer and generated your license keys. Upgrading your vCenter Server does not require any host or VM downtime.
BACKING UP KEY FILESIn addition to a database backup, you should also back up the following key files in case you need to roll back to the previous version.
298 CHAPTER 12 UPGRADING TO VSPHERE Back up the SSL certificate folder under %ALLUSERSPROFILE%\Application G
C:\Program Files\VMware\VMware License Server\Licenses.
Make note of your ODBC DSN, username, and password.
AGENT PRE-UPGRADE CHECK TOOLAs part of the upgrade to vCenter Server, all of the hosts that are managed by it must have their vCenter Server agent (vpxa) that is running on them upgraded as well. It is fairly common to have this process fail on some hosts for various reasons, and as a result, they become disconnected from vCenter Server after the upgrade. When this happens you can manually get the agent to install, but the Agent Pre-upgrade Check tool is available that is designed to prevent the failure from happening. The tool checks each host for some of the usual things that cause the agent installation to fail. This includes making sure the host has sufficient disk space on the Service Console partitions, the host is reachable, the filesystem is intact, and any required patches are applied.
You can launch the tool from the vCenter Server installer; it is listed under Utility. Once you run the tool, it goes out to VMware’s website and downloads any new updates that are available for it. When the wizard launches follow these steps to complete it.
running on them. Once the scan completes, click the Next button to see the results.
4. At the Pre-check screen, you will see your hosts listed as the results of the test. Click the links to see each host’s individual report, or click the Run Report button for the full results.
If any of the hosts fail, read the results and resolve any issues with them. When you’re finished, you’re ready to upgrade vCenter Server.
RUNNING THE VCENTER SERVER INSTALLERWhen you are ready to begin the upgrade, run the vCenter Server 4.0 installer by running the autorun.exe file on the install media. From the vSphere vCenter Server installer menu, choose the vCenter Server product installer and follow these steps.
1. At the Welcome screen, the installer will detect a previous vCenter Server version. Click Next to begin the upgrade.
2. At the License Agreement screen, accept the agreement and click Next.
3. At the Customer Information screen, enter your information and optionally enter a vCenter Server 4.0 license key. If you do not enter one, you can always enter one later, as it will use a 60-day evaluation key instead. Click Next to continue.
4. At the Database Options screen, the ODBC DSN that is already used by vCenter Server will be selected and you must provide a username/password if you are using SQL authentication; if you are using Windows authentication, you can leave this field blank. If you are using the built-in database, you can leave those fields blank also. Click Next to continue.
5. You may receive a message that some of the existing extensions (e.g., Update Manager, Converter) will not be compatible after the upgrade. You can upgrade them manually afterward using the vCenter Server product installer. Click OK to continue.
6. At the Database Upgrade screen, you have an option to upgrade the existing vCenter Server database. If you choose not to upgrade, you cannot continue, as the database upgrade is required. You also must check the box confirming that you have backed up your database and SSL certificates before you can continue. This screen is meant as a final warning to let you know your database will be upgraded, and if you do not have a backup, you cannot roll back to vCenter Server 2.x. Click Next to continue.
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7. At the vCenter Server Service screen, either accept the default to use the built-in SYSTEM account or specify a user domain account instead. Click Next to continue.
8. At the Configure Ports screen, you have the option to change any of the default port numbers that are used by vCenter Server. It’s recommended that you leave these at the defaults, unless you have changed the ports on your other servers because of a conflict. Be aware that if you are running another web server on the vCenter Server, such as Microsoft Internet Information Services (IIS), ports 80 and 443 will conflict with vCenter Server’s built-in Tomcat web server. Click Next to continue.
9. At the Ready to Install screen, click the Install button to begin the upgrade.
Your database will be upgraded as part of the vCenter Server installation. If you are upgrading from vCenter Server 2.5, the Database Upgrade Wizard runs in the background and requires no interaction. If you are upgrading from vCenter Server 2.0.x, the Database Upgrade Wizard appears and you must complete the wizard. If the Database Upgrade Wizard does display, you will have the option to keep the existing performance data, discard it, or keep only the last 12 months of it. If you keep the data, the upgrade will take quite a while if there is a lot of old performance data in the database.
10. The installer will run and will install and configure various components as well as upgrade the database. Once it completes, click Finish and the wizard will close. You will need to restart the system next.
POST-INSTALLATION STEPSOnce the vCenter Server restarts, you will need to connect to it using the vSphere Client. If you try to connect with the VI3 Client, you will get an error message stating that the required client support files need to be retrieved from the server and installed. You can run the vSphere Client installer by choosing the Run the Installer option; you can also download it and run it manually. In addition, you can access the vSphere Client installer from the vCenter Server install image or by accessing the vCenter Server with a web browser. When you run the vSphere Client installer you will also have the option to install the Host Update utility which you can use to upgrade hosts from VI3 to vSphere.
anything, as this is taken care of automatically, even if your license server is on another server. You should verify, though, that your VMware License Server service is running.
If you uninstalled vCenter Server or did a clean installation, you will need to configure the legacy licensing support. To do this select vCenter Server Settings under the Administration section and then select Licensing in the left pane. In the right pane, you can enter the IP address/host name of a new or existing VI3 licensing server and check the option to Reconfigure ESX 3 hosts.
You can verify that the VI3 licenses are being read by selecting Licensing under the Administration section. All your VI3 licenses should be displayed in the Product view.
After the installation, if you are using an Oracle database, you should copy the Oracle JDBC Driver (ojdbc14.jar) to the VMware vCenter Server\tomcat\lib folder. For SQL Server databases, if you enabled bulk logging for the upgrade, disable it after the upgrade is complete.
Finally, you will want to upgrade your extensions to the new vSphere versions.
To do this, run the vCenter Server 4.0 installer and select each extension. You can install the Update Manager, Converter, and Guided Consolidation extensions. When you run the installation, the installer will detect the old version of each extension and automatically upgrade it. After you upgrade the extensions, you must also upgrade the plug-in component in each vSphere Client instance by going to the Plug-in Manager and installing the new plug-ins.
PHASE 2: UPGRADING ESX AND ESXIYou have several options for upgrading your ESX and ESXi hosts to vSphere.
The first option is to use the Update Manager plug-in that comes with vCenter Server. The second is to use the Host Update utility that installs with the vSphere Client that is normally used to patch/upgrade ESXi hosts. The Host Update utility is typically used to patch stand-alone hosts when vCenter Server is not being used, but in vSphere, it can now upgrade VI3 ESX hosts to vSphere as well. The final option is to simply burn the vSphere install ISO to a DVD, boot the host from it, and run through the installer.
Update Manager is much more robust than the Host Update utility, and you can orchestrate upgrades so that both hosts and VMs are updated. You can schedule upgrades via Update Manager, and automation and workflow are built 302 CHAPTER 12 UPGRADING TO VSPHERE into it to make the process much easier. The Host Update utility provides an easy way to upgrade hosts from a remote location, without a CD, and with minimal down time. The utility upgrades the VMkernel and the service console on ESX hosts, and upgrades the image of ESXi hosts. It does not upgrade VMFS datastores, VM hardware, or VMware Tools, as Update Manager does.
USING THE HOST UPDATE UTILITYThe Host Update utility is an optional add-on when installing the vSphere Client. If you do not have it, you can simply reinstall the vSphere Client to install it.1 Once you are ready to use it to upgrade your host, follow these steps.
1. Launch the Host Update utility and you will first be prompted that the utility needs to download patches from the VMware patch repository. Click No for this, as we are using the utility to upgrade hosts and not patch them.
2. From the top menu, select Host and then select Add Host and enter the IP address/host name of the host you wish to update. The host information will be displayed; note that patching is supported only for ESXi hosts and not for ESX hosts, but you can use the utility to upgrade ESX hosts.
3. You will need to put the host in maintenance mode before you can upgrade it, so shut down the VMs on the host or move them to other hosts before proceeding.