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Category Archives: Highlights

Disk is already managed by View

Horizon ViewToday we will highlight one of our KB articles that is getting some traction with our Horizon View customers. The  issue can occur if the ADAM database contains an invalid entry for a persistent disk.


  • Attempting to import the disk from vCenter Server fails with the error:
This disk is already managed by View
  • Cannot detach a Persistent User Data Disk in View Manager.
  • Cannot import a Persistent Disk from vCenter Server for a virtual machine that was deleted in View Administrator.
  • The Persistent disk is visible when the option to show incompatible files is selected.

If you are encountering any of these symptoms in your environment, please refer to KB article: Cannot detach a Persistent Disk in View Manager 4.5 and later (2007076). This article has a 5 star customer rating.

Note: This KB contains two Warnings. Be sure you completely understand the article, and as always check that your backups are working and are valid.

Scan and fix provisioning errors with ViewDbChk tool

Normally, View Administrators can recover from errors that occur during provisioning or other operations by removing or resetting a desktop virtual machine using View Administrator. On rare occasions, the information in the different databases about a machine that is in an error state might become inconsistent and it is not possible to recover from the error using View Administrator. In situations where database inconsistencies cause a desktop machine to be in an unrecoverable error state or prevent a View Administrator task from completing successfully, you can use the ViewDbChk command to resolve the inconsistencies.

In a View environment, information about desktop virtual machines is stored in three places:

  • The LDAP database
  • The View Composer database
  • The vCenter Server database

We’ve created a new Knowledgebase article specifically for this tool: Removing invalid linked clone entries automatically using the ViewDBChk tool in VMware Horizon View 5.3 and later versions (2118050).

Note: For Horizon View 6.1 and later, the ViewDbChk tool is included with your View Connection Server installation. For Horizon View 5.3 and 6.0, you must download the tool from the VMware Labs ViewDbChk fling page.


Ghost – glibc gethostbyname* buffer overflow

In case you missed it, on January 27th, 2015 a buffer overflow vulnerability in the glibc gethostbyname() function was disclosed. The issue is identified by CVE-2015-0235 and was given the name “Ghost.”

The VMware Security Engineering, Communications, and Response group (vSECR) began investigating this issue immediately.

The security blog at VMware released a blog post concerning this vulnerability, and a KB article was published:
VMware Response to CVE-2015-0235 – glibc gethostbyname buffer overflow, aka “Ghost” (2105862).

VMware has an established software security engineering group that integrates these techniques into the software development cycle, provides security expertise, guidance on the latest security threats and defensive techniques, and training within the development organization. This group is also responsible for driving VMware products through external security accreditations and certifications.

Many VMware products, including vSphere™, VMware vCenter™ Server, and vCloud Networking and Security (vCNS) have achieved Common Criteria certification under the Common Criteria Evaluation and Certification Scheme (CCS).Common Criteria is an international set of guidelines (ISO 15408) that provides a common framework for evaluating security features and capabilities of Information Technology (IT) security products.

For more information, visit VMware’s Common Criteria and FIPS-140 Certifications.

Popular tweets

Here’s an interesting top 20 list. In the last 30 days, these were the tweets form our @vmwarekb account that got the most sharing from our customers. Perhaps you missed something on our list you’d be interested in.

Oh, and if you don’t follow us on Twitter, why not?

How to restart the Management agents on a VMware vSphere ESXi or ESX host
Poor network performance when using VMXNET3 adapter for routing in a Linux guest operating system (2077393)
Configuring the ESXi host with Active Directory authentication
Configuring the ESXi host with Active Directory authentication (2075361)
ESXi host initiates ARP Broadcast storm to NFS server (2080034)
Veeam virtual machine backups fail with the error: The host is not licensed for this feature (2080352)
Downgrading device drivers in VMware ESXi 5.x (2079279)
ESXi 5.5 … purple … screen error:#PF Exception 14 in world 33426: vmkeventd IP 0x418002c71507 addr 0x0 (2061842)
Storage Controllers previously supported for VSAN that are no longer supported (2081431)
VMware ESXi 5.1, Patch Release ESXi510-201406001 (2077640)
VM loses network connectivity during migration … in vCNS 5.1.4 and 5.5.2 and NSX for vSphere 6.0.4 (2080479)
Copying a file is slow on HTTP connections in vCenter Server (2081624)
VMware ESXi host in the vSphere Distributed Switch (vDS) are out of sync (2081052)
Preparing Windows 2008 R2 SP1 Server as a desktop to be deployed by Horizon DaaS (Desktone) (2080765)
Adding an Integrated Active Directory (IWA) Identity Source without the vSphere Web Client for vCenter SSO (2063424)
Upgrade paths and product compatibility for PowerCLI versions that feature OpenSSL security fixes (2082132)
Upgrading VMware vCenter Server 5.5 to a 5.5.x version using Simple Install fails (2074676)
VMware ESXi 5.1, Patch ESXi-5.1.0-20140604001-standard (2077642)
Dell EqualLogic Multipathing Extension Module (MEM) in View environments storage performance degradation (2078451)
Booting the ESXi host fails at Initializing scheduler (2077712)

vSphere 5.5 is here! – KBs you need to know about

vSphere 5.5 has been released for all to download. We’re sure vSphere users are all eager to install a copy and start kicking the tires, and we’re just as eager to see that you get started on the right foot. With this in mind, we have created the following list of Knowledgebase articles that are brand new, or have been updated for vSphere 5.5 You’ll notice lots of best practices KBs here.

The first grouping contains absolute ‘must know’ information, the second grouping gets a bit more into details.

Also not to be missed:

New Network port diagram for vSphere 5.x

Over the past few weeks we have been working on constructing a brand new network diagram, depicting ports in use for vSphere 5.x

These diagrams have been very popular in the past and we hope you like this one too! We created Knowledgebase article: Network port diagram for vSphere 5.x (2054806) as a container for the pdf diagram. The pdf also lists all of the ports used in tabular format.

If you’d like to see more of these, tell us in the comments section below!

Network port diagram for vSphere 5

Alternate download location.

Note: This information provided is on a best effort basis. VMware will endeavor to update the diagram as new releases come out.

Trending Issues in ESXi and vCenter Server

As we spoke about in this announcement, here are our currently trending KB articles related to ESXi and vCenter Server. These are the issues the majority of users are encountering. See anything familiar?

Trending Issues in VMware Fusion

Something you’re going to see starting today are a new breed of KB articles, titled “Trending Issues: <topic of interest>“. Our plan is to run reports on incoming support traffic and determine which KB articles are used most often. As well, we are interviewing our front-line support engineers and asking what issues they are experiencing the most. The plan is once they are established to update them periodically, depending on the trends we see.

Our first set of articles will be of interest to our users of VMware Fusion.

How to deploy SSO in a multisite configuration

For those of you administering multiple vSphere environments, getting a SSO multisite deployment up and running in a correct configuration is very important. Multisite deployments are where a local replica is maintained at remote sites of the primary vCenter Single Sign-On instance. The process of setting this up is not complicated, but it is possible to take a wrong turn and end up wasting a whole lot of time correcting it. That is why we have created a best-practice Knowledgebase article titled: Multisite Single Sign-On deployment best practices. (2042849). We highly recommend you look at the examples in that article.

We’ve written extensively in this blog about SSO in the past. You can see all the other posts on the topic here: http://blogs.vmware.com/kb/tag/sso

If you are still at the point where you are asking yourself- what is SSO? and why do I care? we recommend you start with this great introduction from Justin King: vCenter Single Sign-On Part 1: what is vCenter Single Sign-On?

Top 10 KB Articles for Infrastructure

The following three lists of Knowledgebase articles comprise our top 10 articles that our Infrastructure Support Engineers are using to solve customer Support Requests during the month of January. When we say Infrastructure, it’s more of an internal term we use to group support teams. The Infrastructure guys cover issues including storage, networking, and system faults (crashes).

The first list is the overall top ten. The second and third lists are known infrastructure issues and how-to / informational KB articles that apply to ESXi 5.1 and vCenter Server.

Top 10 Infrastructure Articles (ESX/i 3.x/4.x/5.x, vCenter Server)

  1. Broadcom 5719/5720 NICs using tg3 driver become unresponsive and stop traffic in vSphere (2035701)
  2. Unmounting a LUN or Detaching a Datastore/Storage Device from multiple ESXi 5.x hosts (2004605)
  3. Installing async drivers on ESXi 5.x (2005205)
  4. Investigating virtual machine file locks on ESXi/ESX (10051)
  5. Using esxtop to identify storage performance issues (1008205)
  6. Recreating a missing virtual machine disk (VMDK) descriptor file (1002511)
  7. Commands to monitor snapshot deletion in ESX 2.5/3.x/4.x and ESXi 3.x.x/4.x.x/5.x (1007566)
  8. Committing snapshots when there are no snapshot entries in the Snapshot Manager (1002310)
  9. Permanent Device Loss (PDL) and All-Paths-Down (APD) in vSphere 5.0 (2004684)
  10. Creating a snapshot for a virtual machine fails with the error: File is larger than maximum file size supported (1012384)

Top 10 vSphere 5.1 Infrastructure known issues

  1. Broadcom 5719/5720 NICs using tg3 driver become unresponsive and stop traffic in vSphere (2035701)
  2. Unmounting a LUN or Detaching a Datastore/Storage Device from multiple ESXi 5.x hosts (2004605)
  3. Creating a snapshot for a virtual machine fails with the error: File is larger than maximum file size supported (1012384)
  4. ESXi/ESX hosts with visibility to RDM LUNs being used by MSCS nodes with RDMs may take a long time to boot or during LUN rescan (1016106)
  5. An ESXi/ESX host reports VMFS heap warnings when hosting virtual machines that collectively use 4 TB or 20 TB of virtual disk storage (1004424)
  6. ESXi 5.x host fails with a purple diagnostics screen when using Intel(R) Xeon(R) CPU E5-2### and E5-46## (2033780)
  7. ESX/ESXi hosts might experience read/write performance issues with certain storage arrays (1002598)
  8. vHBAs and other PCI devices may stop responding in ESXi 5.x and ESXi/ESX 4.1 when using Interrupt Remapping (1030265)
  9. ESXi 5.x hosts fail to mount VMFS5 volumes that are formatted with ATS-only capabilities (2006858)
  10. Cannot take a quiesced snapshot of Windows 2008 R2 virtual machine (1031298)

Top 10 vSphere 5.1 Informational/How To Articles

  1. Installing async drivers on ESXi 5.x (2005205)
  2. Investigating virtual machine file locks on ESXi/ESX (10051)
  3. Using esxtop to identify storage performance issues (1008205)
  4. Recreating a missing virtual machine disk (VMDK) descriptor file (1002511)
  5. Commands to monitor snapshot deletion in ESX 2.5/3.x/4.x and ESXi 3.x.x/4.x.x/5 .x (1007566)
  6. Permanent Device Loss (PDL) and All-Paths-Down (APD) in vSphere 5.0 (2004684)
  7. vSphere handling of LUNs detected as snapshot LUNs (1011387)
  8. Best practices for virtual machine snapshots in the VMware environment (1025279)
  9. Manually regenerating core dump files in VMware ESXi/ESX (1002769)
  10. Determining Network/Storage firmware and driver version in ESXi/ESX 4.x and 5.x (1027206)