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VCP 5 Objective 1.3 – Plan and Perform an Upgrade of vCenter Server and VMware ESXi

without comments

This section uses the following tools based on the VMware VCP 5 Blueprint:

Things to know:

1. Upgrade requirements for ESXi hosts

  • Minimum Hardware Requirements
    • Supported server platform on the vSphere Hardware Compatibility List
    • 64-bit x86 CPUs
    • 2 single core CPUs or 1 dual core CPU
    • CPUs must support LAHF (Load AH from Flags) and SAHF (Store AH into Flags)
    • Minimum 2 GB RAM
    • At least one 1 GB or 10 GB ethernet controllers listed in the VMWare HCL
    • One or more basic SCSI controller or RAID controller
    • SCSI Disk or a local, non-network, RAID LUN with unpartitioned space for the virtual machines
    • For SATA disks a disk connected through supported SAS controllers or supported on-board SATA controllers
  • Storage System Requirements
    • SATA disk drives connected behind supported SAS controllers or supported on-board SATA controllers
    • Serial Attached SCSI (SAS) disk drives
    • Dedicated SAN disk on Fibre Channel or iSCSI
    • USB Devises listed in the VMWare HCL
    • The selected boot device should be at a minimum of 1GB in size
    • booting from a local disk or SAN/iSCSI LUN, a 5.2GB disk is required to allow for the creation of a VMFS volume and a 4GB scratch volume (/scratch will be moved to the ESXi host ramdisk)
  • ESXi Booting Requirements
    • vSphere 5.0 supports booting ESXi hosts from the Unified Extensible Firmware Interface (UEFI) from hard-drives, CD/DVD-ROM or USB Media.
    • Network boot or AutoDeploy provisioning requires legacy BIOS firmware and is not UEFI compatible
    • Booting from disks larger than 2TB is supported only if the system firmware and any add-on cards install support it.
    • Note: changing the boot type from legacy BIOS to UEFI after you install ESXi 5.0 might cause boot failure on the host
  • Identify Upgrade Path
Upgrade Method ESX/ESXi 4.x to ESXi 5 ESXi 5.0 to ESXi 5.x
vSphere Update Manager Yes Yes
Interactive Upgrade Yes Yes
Scripted Upgrade Yes Yes
vSphere AutoDeploy No Yes
esxcli No Yes


  • List of Files migrated during upgrade
File Notes
CIM ”indication”conf files
/etc/syslog.conf Migrated for ESXi, not migrated for ESX.
/etc/security/access.conf Needed for PAM configurations.
/etc/security/ No comment.
/etc/sysconfig/network Service Console NICs  are converted to VMkernel NICs.
/etc/sysconfig/keyboard Any entries not supported will default to English.
/etc/ssh OpenSSH is now included in ESXi 5.0.
/etc/nsswitch.conf Used generically for various configurations, most helpful for Active Directory authentication.
/etc/krb.conf Needed for Likewise to have Active Directory support.
/etc/krb.realms Needed for Likewise to have Active Directory support.
/etc/krb5.conf Needed for Likewise to have Active Directory support.
/etc/krb5.acl Needed for Likewise to have Active Directory support.
/etc/krb5.keytab Needed for Likewise to have Active Directory support.
/etc/krb5.log Needed for Likewise to have Active Directory support.
/etc/krb5.mkey Needed for Likewise to have Active Directory support.
/etc/pam.d/* (Partial) Needed for authentication and authorization.
Note: Custom edits made to settings in /etc/pam.d/system-auth in ESX 4.x are reset to the default values by the upgrade to ESXi 5.0. To maintain the custom values, reset them manually after the upgrade.
/etc/snmp/snmpd.conf Migrated to /etc/vmware/snmp.xml.
etc/motd A note is appended saying the system was upgraded to ESX 5.x.
/etc/likewise/* Used for Likewise configurations.
/etc/vmware/vmauth/authentication.conf Used for Likewise configurations
/etc/vmware/vmauth/provider.xml Used for Likewise configurations
/etc/fstab (Partial) Only NFS entries will be migrated to ESXi.
/etc/passwd (Partial) Only the root user password will be saved, if possible.
/etc/shadow Only the root user password will be saved, if possible


2. Steps required to upgrade a vSphere

  • Upgrade vCenter Server
    • upgrade from vCenter 4.1 is possible as long as it is installed on a 64 bit Server operating system.  If not,
  • Upgrade or install VMware Update Manager to handle the hosts upgrade/migration
  • Upgrade/migrate/re-install ESXi on the physical hosts
  • Upgrade VMware Tools in all VMs.  Although strictly not mandatory, it is highly recommended
  • Upgrade VMFS filesystem
    • Note: ESXi 4.x hosts cannot read VMFS 5 datastores although ESXi 5 hosts can read VMFS 3 datastores.  Carry out the upgrade of VMFS datastores only after all hosts have been upgraded to vSphere 5.x
  • Upgrade of virtual hardware in virtual guests to version 8.
    • This is an optional task and requires guest downtime as the guests need to be powered off to perform the upgrade. vSphere 5 can run virtual guests running virtual hardware version 7 and version 4.

Note:  vSphere Update manager can orchestrate update of hosts, VMware Tools on virtual guests and VM virtual hardware version updates.

3. Upgrade Networking & vDistributed Switches.

Upgrading a vSphere distributed switch will allow you to take advantage of new features available in vSphere 5 such as support for NetFlow 5, port mirroring and enhancements to the network I/O control functionality such as QoS to I/O shares to user defined traffic among others.  For a full list of enhancements and details look at the What’s New in VMware vSphere 5.0 Networking whitepaper.

Depending on the current version of vSphere there are a couple of upgrade options that may available:

  • vSphere Distributed Switch Version: 4.1.0: compatible with vSphere ESX/ESXi 4.1 and above
  • vSphere Distributed Switch Version: 5.0.0: compatible with vSphere ESXi 5.0 and above
  • Procedure
    • From the vSphere client select Networking from the Inventory section
    • Select the vDistributed Switch from the left hand pane and click Upgrade
    • Follow the prompts on the Upgrade vDistributed Switch to newer version wizard and select the version of vDistributed switch you want to upgrade to.   The wizard will list all the hosts associated with the vDistributed switch and highlight if they are compatible with the upgrade.  The wizard will go ahead with the upgrade only when all hosts associated with the vDistributed switch are compatible.
    • Click Next, then Finish to complete the upgrade process.

Detailed upgrade procedure can be found on pages 26 & 27 of the vSphere Networking Guide.

4. Upgrade the VMFS file system from VMFS3 to VMFS5

VMFS 5 introduces many architectural changes to enhance scalability and performance while reducing complexity.  Some of the more significant changes when compared to VMFS3 are:

Feature VMFS3 VMFS5
Maximum extent volume size 2TB 64TB
Support for pass-through RDMs larger than 2TB No Yes
Subblock for space efficiency Yes (64KB with a max ~3K) Yes (8KB with a max ~30K)
Small-file support No Yes (1KB)
Unified block size No Yes






For a more detailed comparison review the What’s New in VMware vSphere 5.0 – Storage white paper

The upgrade is an online, non-disruptive process which allows the virtual guests to continue to run on the datastore.   When upgrading from VMFS3 to VMFS5 the existing VMFS3 block size will be maintained along with the MBR partition schema.  VMFS5 however uses the GPT partition schema and is available on new datastores formatted with VMFS5

  • Pre-Requisites
    • If you use a VMFS2 datastore, you must first upgrade to VMFS3 before upgrading to VMFS5
    • All hosts accessing the datastore must support VMFS5
    • The volume being upgraded must have at least 2MB of free blocks and 1 free file descriptor
  • Procedure
    • In the vSphere Client select the a host and click on the Configuration tab
    • Click on Storage and select the VMFS3 datastore to be upgraded
    • Click on the Upgrade to VMFS5 link followed by OK on the Upgrade VMFS dialog box
    • Verify the Upgrade VMFS task has completed successfully and re-scan all hosts that have the datastore presented.

For a detailed description read pages 120 & 121 of the vSphere Storage Guide

5. Orchestrate the upgrade of vSphere ESX/ESXi Hosts Using vSphere Update Manager

vSphere Update Manager can be used to perform orchestrated upgrades of vSphere ESX/ESXi 4.x hosts in your vSphere inventory by using a single upgrade baseline.  Upgrade baselines can be created using vSphere ESXi 5.x images that are imported into the Update Manager repository.  Details on how to create and import baselines will be covered in a later post.

Some of the caveats to upgrading hosts using the vSphere Update Manager are:

  1. ESX/ESXi 3.x hosts need to be updated to ESX/ESXi 4.x before update manager can upgrade them to 5.x
  2. Update Manager cannot upgrade a ESX/ESXi host that was previously upgraded from version 3.x with an incompatible partition layout (i.e. /boot with less than 350 MB free space)
  3. The  installation location of the hypervisor cannot be modified.
  • Prerequisites
    • Make sure your system meets the requirements for vCenter Server 5.0, ESXi 5.0, and Update Manager 5.0.
    • Install or upgrade vCenter Server to version 5.0.
    • Install or upgrade vSphere Update Manager to version 5.0
  • Procedure

This is a long section and in the interest of time and brevity the procedure is being described a very high level.

    • Configure Host Maintenance Mode Settings:  host updates might require that the host enters maintenance mode before they can be applied.  Update manager needs to be configured to respond appropriately if the host fails to enter maintenance mode for any reason
    • Configure Cluster Settings: Certain features enabled on an ESX cluster can cause the upgrade to fail.  Features like VMware DPM, HA admission control, or Fault Tolerance may need to be temporarily disabled before the upgrade can start.
    • Enable Remediation of PXE Booted ESXi 5.0 Hosts:  configure Update Manager to let other software initiate remediation of PXE booted ESXi 5.x hosts
    • Import Host Upgrade Images and Create Host Upgrade Baselines:  create upgrade baselines for ESX/ESXi hosts with ESXi 5.x images that you import to the Update Manager repository
    • Create a Host Baseline Group: if multiple patches need to be installed along with the upgrade create a baseline group
    • Attach Baselines and Baseline Groups to Objects: attach existing baselines and baseline groups to vSphere object (hosts, virtual machines, virtual appliances etc) to view compliance information
    • Manually Initiate a Scan of ESX/ESXi Hosts
    • View Compliance Information for vSphere Objects
    • Remediate Hosts Against an Upgrade Baseline or Baseline groups

Detailed process on carrying out an upgrade using upgrade manager can be found on pages 96 – 107 of the vSphere Upgrade Guide


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Written by totalcaos

January 10th, 2013 at 1:08 pm

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