vSphere 5.5 “Best Of” Highlights & Gotchas – Part 1


by Bill Oyler | 12.02.2013
Categories: Blog

Less than a month after VMworld 2013, VMware officially released vSphere 5.5, and its adoption is now starting to be seen in the field. Backup solution vendors and other third party software developers are busy making sure their products are compatible with the new features and APIs present in vSphere 5.5. VMware is also busy updating their various compatibility and interoperability matrixes to include all of the hardware and software configurations supported by vSphere 5.5. To help get everyone excited about upgrading to vSphere 5.5, I am going to hit a few of the “highlights” and “gotchas” in vSphere 5.5 through this two-part blog post.

GOTCHA #1: Be sure to check the Interoperability Matrix and Compatibility Matrix!

Not all products are compatible with vSphere 5.5, including some of VMware’s own products. Also, not all hardware products are compatible with vSphere 5.5. Check out these matrixes before beginning a vSphere 5.5 upgrade or deployment.
Compatibility Guide

Product Interoperability Matrix

Also be sure to check your backup software vendor to ensure they support vSphere 5.5, as well as any third-party products with “hooks” into vSphere or vCenter.

GOTCHA #2: Be sure to review the “update sequence” guide!

VMware has a very specific order in which they would like you to upgrade your VMware software components. If you deviate from this sequence, bad things can happen. Be sure to follow this official KB article very carefully.

Update sequence for vSphere 5.5 and its compatible VMware products (2057795)

HIGHLIGHT #1: More Scalable vCenter Server Appliance (vCSA)

  • The embedded PostgreSQL database now supports up to 100 ESXi hosts and 3,000 VMs. (In 5.0/5.1, the limit was 5 ESXi hosts or 50 VMs).
  • In contrast, the Windows-based vCenter using the SQL Express database still only supports 5 ESXi hosts or 50 VMs.
  • GOTCHA #1: The vCenter Server Appliance does not support vCenter Linked Mode. If Linked Mode is important, you will need to use the Windows-based vCenter.
  • GOTCHA #2: You still need a Windows VM to serve as the Update Manager Server, and you also need a SQL database for Update Manager, so if you want an “all-in-one” deployment of vCenter, using a Windows-based vCenter and a fully licensed copy of SQL Standard/Enterprise is still the best option.

HIGHLIGHT #2: 62 TB VMDKs & Virtual RDMs

vSphere 5.5 now supports VMDKs and Virtual Mode RDMs up to 62 TB in size. (In the past, VMDKs and Virtual RDMs were required to be sized just under 2 TB.) However, there are a handful of “gotchas” to watch out for:
  • 62 TB VMDKs require VMFS-5 or NFS datastores.
  • On NFS, the upper limit is the lesser of 62 TB or 1% less than the maximum file size supported by the NFS server. For example, some NFS servers only support 16 TB file sizes, in which case the limit would be ~16,220 GB (16,384 GB minus 1%).
  • A VMDK larger than 2 TB can be created on a virtual machine that is powered on or off, but extending a VMDK beyond 2 TB is only supported when the virtual machine is powered off
  • You must use the vSphere Web Client to create or extend VMDKs beyond 2 TB.
  • vSphere Flash Read Cache supports a maximum hard disk size of 16 TB.
  • VMware Fault Tolerance is not supported.
  • VMware Virtual SAN is not supported. 
  • BusLogic parallel controllers are not supported.
  • The underlying Guest OS disk format must be GPT to support sizes beyond 2 TB. Most Windows VMs today are using the legacy MBR disk format, and there is no Microsoft native tool to convert from MBR to GPT without data loss. Third party tools will need to be used to convert existing volumes from MBR to GPT without data loss.
  • For Windows NTFS volumes, you must format the volume with an allocation size of 16K in order to use a volume as large as 62 TB. Allocation sizes can only be changed by reformatting the volume in Windows (or using a third-party utility).
    • 8K allocation size supports volumes up to 32 TB for NTFS.
    • 4K allocation size supports volumes up to 16 TB for NTFS.

HIGHLIGHT #3: vSphere Replication Enhancements

(NOTE: The vSphere Replication features listed below are available as part of vSphere Essentials Plus and above licensing, as well as with Site Recovery Manager 5.5.)
  • Ability to preserve multiple point-in-time (PIT) images of VMs that are protected with vSphere Replication.
    • Not available with array-based replication.
    • Maximum of 24 historical point-in-time images can be preserved at recovery site.
    • MPIT retention policy specifies how many to keep over a certain period of time. For example, keep up to 24 hourly snapshots over a 24 hours period of time.
    • vSphere Replication does not replicate virtual machine snapshots, but rather creates new “MPIT” snapshots at the recovery site.
  • Full support for Storage vMotion and Storage DRS on Protected Objects (not Recovery Objects).
    • WAN replication traffic is minimal because ESXi and VR tracks the VM’s movement, so only delta changes are transmitted.
    • This is significantly more flexible than array-based replication, which triggers a “Full” VM replication when you perform a Storage vMotion of a VM.
  • Ability to protect VMs with disks that are larger than 2TB.
  • Dramatic speed improvement in vSphere Replication. New algorithms make the performance of vSphere Replication even more efficient than in the past.

HIGHLIGHT #4: Microsoft Clustering Improvements

  • VMware now supports the iSCSI and FCoE protocols for shared disk access in Microsoft Cluster deployment scenarios. (In the past, only Fibre Channel was supported.)
  • VMware now supports the “Round Robin” multipathing policy on Microsoft Cluster shared LUNs.
  • VMware now supports Windows 2012 clusters running on vSphere hosts.
  • VMware now supports using a Microsoft SQL Cluster to host the vCenter database. Be sure to follow instructions in KB#2059560. (Previously, using Microsoft SQL Cluster was not supported for any version of vSphere.)
Be sure to always follow the official VMware guidelines (below) when configuring Microsoft Clustering on VMware.

Microsoft Clustering on VMware vSphere: Guidelines for supported configurations (1037959)

Microsoft Cluster Service (MSCS) support on ESXi/ESX (1004617)

HIGHLIGHT #5: Re-Written Single Sign-On

  • Single Sign-On has been complete re-written! It is far more user-friendly than in vSphere 5.1.
  • No more RSA database or RSA SQL user accounts for SSO! SSO now uses an embedded database.
  • SSO is now site aware. You specify a site name during installation of each SSO server.
  • SSO servers now have the ability to automatically synchronize authentication data across sites.

HIGHLIGHT #6: Web Client

In vSphere 5.5, the Web Client is becoming more of a “first-class citizen.” Remember, to use all new features in vSphere 5.1 and 5.5, you MUST use the Web Client. So this is the perfect time to get accustomed to it. Some improvements include:
  • The Web Client is MUCH faster and more responsive than in the past.
  • Drag-and-drop is now fully supported.
  • Mac OS is now fully supported, including remote console viewing, using Firefox and Chrome web browsers.
In my next blog post, I will cover the exciting new “VSAN” and “vSphere Flash Read Cache” features available in vSphere 5.5.