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How to recreate a missing vmdk AKA virtual machine disk descriptor file

This video tells you how to recreate a missing virtual machine disk descriptor, also know as the vmdk file.

Note: VMware recommends to attempt to restore the missing descriptor file from backups if possible. If this is not possible, proceed with recreating the virtual machine disk descriptor file.

Watch the video to see the steps taken to create a virtual machine disk descriptor file:

  • Identify the size of the flat file in bytes.
  • Create a new blank virtual disk that is the same size as the original. This serves as a baseline example that is modified in later steps.
  • Rename the descriptor file (also referred to as a header file) of the newly-created disk to match the name of the original virtual disk.
  • Modify the contents of the renamed descriptor file to reference the flat file.
  • Remove the leftover temporary flat file of the newly-created disk, as it is not required.

This procedure will not work on virtual disks configured with a Para-virtualized SCSI controller in the virtual machine

NSX for vSphere Field Advisory – October 2016 Edition

For more information, see the NSX for vSphere 6.2.4 Release Notes on all issues listed below.

There is a security vulnerability issue that was found in OpenSSL that is used in VMware NSX for vSphere 6.2.4. For more information, see https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2107.

** Reminder – vShield Endpoint Update **

VMware has announced the End of Availability (EOA) and End of General Support (EOGS) of VMware vCloud Networking and Security 5.5.x. The EOGS date for VMware vCloud Networking and Security 5.5.x is September 19, 2016.  For customers using vCNS Manager specifically to manage vShield Endpoint for agentless anti-virus, Technical Guidance is available until March 31, 2017. For more information, see End of Availability and End of General Support for VMware vCloud Networking and Security 5.5.x (2144733).

Consult the VMware Compatibility Guide for Endpoint partner solution certification status before upgrading. If your preferred solution is not yet certified, please contact that vendor.

Installation and Upgrade Known Issues

Issue 1728633 – Starting in NSX 6.2.3, a third VIB, esx-vdpi, is provided along with the esx-vsip and esx-vxlan NSX VIBs.  A successful installation will include all three VIBs. 

Issue 1730017: Upgrades from 6.2.3 to 6.2.4 do not show a version change for Guest Introspection.

  • As the 6.2.3 Guest Introspection module is the latest version available, the version after a 6.2.4 upgrade remains unchanged. Note that upgrades from earlier NSX releases may show a version change to 6.2.4. This issue does not affect any functionality.

NSX 6.2.4 virtual machines lose network connectivity (2146171)

  • Virtual machines lose network connectivity after vMotion under the following conditions:
    • Distributed Firewall (DFW) is enabled in the environment and;
    • NSX for vSphere setup upgraded from NSX-V 6.1.x release to NSX-V 6.2.3a/6.2.3b/6.2.4 release and virtual machines are later migrated between upgraded ESXi hosts.
  • For more information, see KB 2146171 for the workaround.

NSX Manager Known Issues

Fixed issue 1489648: NSX is unavailable from the vSphere Web Client Plug-in after taking a backup of NSX Manager with quiesced snapshot

  • Note following important points about NSX backup and restore:
    • Backup/restore functionality provided by NSX is the only supported way to backup/restore the NSX Manager.
    • Taking a snapshot of the NSX Manager with vSphere is a supported operation. However, VMware does not currently test or support any third party tool that takes snapshot of the NSX Manager.
    • Restoring the NSX Manager from snapshot (taken in any way) is not supported.

See also Issue 1708769 and Increased latency on SVM (Service VM) after snapshot in NSX (2146769). There is no need to snapshot an SVM as it does not need to move or be replicated.

Security Services Known Issues

Issue 1718726: Cannot force-sync Service Composer after a user has manually deleted the Service Composer’s policy section using DFW REST API

  • In a cross-vCenter NSX environment, a user’s attempt to force sync NSX Service Composer configuration will fail if there was only one policy section and that policy section (the Service Composer-managed policy section) was deleted earlier via a REST API call.
  • Workaround: Do not delete the Service Composer-managed policy section via a REST API call. (Note that the UI already prevents deletion of this section).

Issue 1707931: Order of distributed firewall rules changes when service policies defined in Service Composer are present, and a firewall rule is modified or published with a filter applied in the Firewall UI

  • Changing the order, adding or deleting service policies created in Service Composer after one or more publish operations are made from the Networking & Security > Firewall UI will cause the order of firewall rules to change and may result in unintended consequences.

Issue 1717635: Firewall configuration operation fails if more than one cluster is present in environment and changes are done in parallel 

  • In an environment with multiple clusters, if two or more users modify the firewall configuration continuously in a tight loop. (for example, Add/Delete sections or rules), some operations fail.

Issue 1732337/1724222: NSX Manager fails to push firewall rules to ESXi 6.0 P03 host

  • NSX Manager fails to push firewall rules to ESXi 6.0 P03 host, and NSX Edge health check fails as vsfwd connection is closed. This is a known issue affecting VMware NSX for vSphere 6.2.x with ESXi 6.0 P03 (Build 4192238). This issue occurs when /dev/random call is blocked which affects NSX operation on password generation.
  • Workaround: Contact VMware technical support. For more information, see vsfwd connection to the NSX Manager fails (2146873).

Issue 1620460: NSX fails to prevent users from creating rules in Service Composer rules section

  • In the vSphere Web Client, the Networking and Security: Firewall interface fails to prevent users from adding rules to the Service Composer rules section. Users should be permitted to add rules above/below the Service Composer section, but not inside it.
  • Workaround: Do not use the “+” button at the global rule level to add rules to the Service Composer rules section.

Issue 1682552: Threshold events for CPU/Memory/CPS for Distributed Firewall (DFW) are not reported

  • Even when the DFW thresholds for CPU/Memory/CPS are set for reporting, the threshold events are not reported when the thresholds are crossed.
  • Workaround:
    • Log in to each ESXi host and restart the DFW control plane process by running the following command:

/etc/init.d/vShield_Stateful_Firewall restart

  • Verify the status using the following command:

/etc/init.d/vShield_Stateful_Firewall status

  • The result similar to following is displayed:

“vShield-Stateful-Firewall is running”

Note: You should be cautious while performing this operation as this will push all DFW rules to all the filters again. If there are lot of rules, it might take some time to enforce them on all the filters.

Logical Networking Known Issues and NSX Edge Known Issues

Issue 1704540 – High volume of MAC learning table updates with NSX L2 bridge and LACP may lead to out of memory condition

  • When an NSX L2 bridge sees a MAC address on a different uplink, it reports a MAC learning table change to controllers through the netcpa process. Networking environments with LACP will learn the same MAC address on multiple interfaces, resulting in a very high volume of table updates and potentially exhausting the memory needed by the netcpa process to do the reporting.
  • Workaround – Avoid setting a flow-based hashing algorithm on the physical switch when using LACP. Instead, pin MAC addresses to the same uplinks or change the policy to source-MAC.

Issue 1717369 – When configured in HA mode, both active and standby Edge VMs may be deployed on the same host.

  • This issue results from anti-affinity rules not being created and applied on the vSphere hosts automatically during redeploy and upgrade operations.  This issue will not be seen when HA is being enabled on existing Edge.
  • In NSX releases with a fix for this issue, the following is the expected behavior:
    • When vSphere HA is enabled, anti-affinity rules for Edge VMs of an HA pair will be created during redeploy, upgrade.
    • When vSphere HA is disabled, anti-affinity rules for Edge VMs of an HA pair will not be created.

Issue 1716545 – Changing appliance size of Edge does not affect standby Edge’s CPU and Memory reservation

  • Only the first Edge VM created as part of an HA pair is assigned the reservation settings.
  • Workaround: To configure the same CPU/Memory reservation on both Edge VMs:
    1) Use the PUT API https://<NSXManager>/api/4.0/edgePublish/tuningConfiguration to set explicit values for both Edge VMs.
    2) Disable and re-enable Edge HA, which will delete the second Edge VM and redeploy a new one with the default reservations.

Issue 1510724: Default routes do not populate on hosts after creating a new Universal Distributed Logical Router (UDLR)

  • After changing NSX Manager from Standalone to Primary mode for the purpose of configuring Cross-vCenter in NSX for vSphere 6.2.x, you may experience these symptoms:
  • When you create a new UDLR, the default routes are not populated on the host instance.
  • Routes are populated on the UDLR Control VM but not on the host instance.
  • Running the show logical-router host host-ID dlr Edge-ID route command fails to show default routes.
  • Workaround: For information on how to recover from this issue, see Default routes do not populate on the hosts after creating a new UDLR (2145959).

Issue 1733146 – Under certain conditions, creating or modifying LIFs for a Universal DLR fails when no control VM exists

  • This issue is known to manifest under the following conditions:
    1. ECMP with two static default routes.
    2. Static routes with local egress flag.
  • This issue results from a full synchronization being requested instead of a delta update, resulting in the rejection of duplicate entities and a failed operation.
  • See the release notes for a workaround.

NSX Edge Load Balancer accepts only approved ciphers as of 6.2.3. 

  • In earlier releases, customer-defined ciphers are supported for ClientSSL and ServerSSL.
  • NSX 6.2.3 introduced an approved ciphers list:
    • AES256-SHA
    • AES128-SHA
    • DES-CBC3-SHA
  • Note the following expected behaviors:
  1. The cipher value will be reset to “DEFAULT” if the cipher is null, empty, or not in approved ciphers suite.
  2. Ciphers included in the approved ciphers suite are passed to the Edge.
  3. When upgrading from a pre-6.2.3 release, a cipher value which is null/empty or not in approved ciphers suite will be reset to “DEFAULT”.

NSX Controller Issues

Data path issues for VNIs with disconnected NSX Controller (2146973)

  • Symptoms – NSX controller shows as disconnected in the vSphere Web Client, leading to data path issues for VNIs handled by the disconnected controller.
  • This issue occurs because IPSec re-keying is disabled in NSX-V 6.1.5, 6.1.6, 6.2, 6,2,1 and 6.2.2 releases to avoid hitting another known IPSec issue.

General Issues

NSX API now returns XML output by default when Accept header is not provided

Beginning in NSX 6.2.3, if the “Accept:” header is not provided in a REST API call, then the default formatting of NSX API return values is XML. Previously the NSX API returned JSON-formatted output by default. To receive JSON-formatted output, the API user must explicitly set “application/json” in the “Accept:” header when calling the function.

** How to track the top field issues **

How to install Windows in VMware Fusion using Easy Install

This video demonstrates how to install Windows guest operating system using the Easy Install feature in VMware Fusion.

Before creating a virtual machine, you must obtain the operating system and any necessary product keys for installation in that virtual machine. VMware Fusion does not come with any operating systems to install in virtual machines you create.

This method assumes that you are using a physical CD or a disk image (.iso / .cdr /.dmg file). You cannot create a Windows virtual machine by using .exe files downloaded from Microsoft, as those files need to be run on a Windows PC.

Troubleshooting Virtual SAN Providers status- Disconnected

This video demonstrates how to troubleshoot Virtual SAN Providers which display the status as disconnected in the vSphere Web Client. This issue occurs if the SMS certificate for vCenter server is expired.

To resolve this issue, expired certificate will be removed and a new certificate will be generated.

Troubleshooting Virtual SAN on-disk format upgrade to 3.0 failures

This video demonstrates how to troubleshoot Virtual SAN on-disk format upgrade to 3.0, which may fail in small Virtual SAN clusters or ROBO/stretched clusters.

Attempting an on-disk upgrade in certain VSAN configurations may result in failure. Configurations that can cause these errors include:

  • The stretched VSAN Cluster consists of two ESXi Hosts and the Witness Node (ROBO configuration)
  • Each Host in the Stretched Cluster contains a single VSAN Disk Group
  • A Virtual SAN cluster consists of three normal nodes, with one disk group per node
  • A Virtual SAN cluster is very full, preventing the “full data migration” disk-group decommission mode

To allow an upgrade to proceed in these configurations, a compromise as to availability must be made. Data accessibility will be maintained, but the redundant copy of the data will be lost and rebuilt during the upgrade process. As a result, data will be exposed to faults and failures such as the loss of a disk on another node may result in data loss. This exposure to additional failure risk is referred to as “reduced redundancy,” and must be manually specified in the Ruby vSphere Console (RVC) to allow the upgrade to proceed. It is not possible to specify reduced redundancy when using the vSphere Web Client to start the upgrade.

Caution: During upgrade, a single point of failure is exposed. Follow all VMware best practices, and your business practices, regarding the backup of important data and virtual machines.

Tips and tricks on Ruby vSphere Console (RVC) for managing a Virtual SAN environment

In this latest KBTV Webinar you will learn some great tips and tricks you can use in Ruby vSphere Console (RVC) for managing a Virtual SAN environment.

Covered in this video demonstration are various commands that can be used within Ruby vSphere Console (RVC), including:

  •  “vsan.disks_stats” Useful for capacity planning, management of disk groups and monitoring the health of physical disks
  •  “vsan.check_state” Useful for troubleshooting data unavailability situations and understanding object health in the VSAN cluster
  •  “vsan.resync_dashboard” Useful for visibility into data resync when changing storage policies
  •  “vsan.whatif_host_failures” Useful for capacity planning on future VSAN nodes and understanding VSAN’s ability to tolerate node failures

Top 20 vSAN articles for September 2016

Top 20Here is our Top 20 vSAN articles list for September 2016. This list is ranked by the number of times a VMware Support Request was resolved by following the steps in a published Knowledge Base article.

  1. Troubleshooting VSAN SSD congestion on vSphere 5.5
  2. VSAN 6.2 hybrid disk group performance degradation
  3. vSphere 5.5 Virtual SAN requirements
  4. How to capture performance statistics using VSAN Observer
  5. Support statement for 512e and 4K Native drives for VMware vSphere and VSAN
  6. Powering on virtual machines in VMware Virtual SAN 5.5 fails with error: Failed to create swap file
  7. Recommended settings for RAID0 logical volumes on certain 6G LSI based RAID VSAN
  8. VSAN 6.1/5.5 Update 3 Disk Groups show as Unmounted in the vSphere Web Client (DDH)
  9. Retaining virtual machines of Virtual SAN Beta cluster when upgrading to vSphere 5.5 Update 1
  10. Cannot view or add VSAN Storage Providers in vSphere Web Client
  11. Virtual SAN Health Service – Data Health – Virtual SAN Object Health
  12. Virtual SAN Health Service – Physical Disk Health – Overall Disk Health
  13. Virtual SAN Health Service – Physical Disk Health – Congestion
  14. Upgrading from VMware vSphere 5.5 EP06 or 5.5 P04 to vSphere 6.0 GA can cause VMware Virtual SAN Data Unavailability
  15. Upgrading Virtual SAN (VSAN) on-disk format from version 1 to 2
  16. “An error occurred while consolidating disks: msg.disklib.NOSPACE” in VSAN
  17. Using Oracle RAC on vSphere 6.x VSAN Datastore
  18. VMware virtual SAN storage provider fails during resyncwith the error: com.vmware.vim.binding.sms.fault.ServiceNotInitialized
  19. Virtual SAN Multicast performance test fails
  20. Shutting down and powering on a VSAN 6.x Cluster when vCenter Server is running on top of VSAN

Top 20 vRealize Operations Manager articles for September 2016

Top 20Here is our Top 20 vRealize Operations Manager articles list for September 2016. This list is ranked by the number of times a VMware Support Request was resolved by following the steps in a published Knowledge Base article.

  1. Optimization of vRealize Operations Manager generated capacity planning metrics in 6.3
  2. Adding additional storage to the VMware vRealize Operations Manager Analytics or UI virtual machine
  3. vRealize Operations Manager Sizing Guidelines
  4. vRealize Operations Manager 6.x is inaccessible, status of all nodes is Waiting for Analytics to Start
  5. Enabling SSH access in vRealize Operations Manager 6.x
  6. Changing a node hostname in a VMware vRealize Operations Manager vApp based cluster
  7. Understanding Feature Accommodation between VMware vSphere 6.0 and vRealize Operations 5.8.x and 6.0.1 Feature Accommodation
  8. Change the IP address on a vRealize Operations Manager 6.0.x single-node deployment
  9. VMware vRealize Operations Manager 6.x displays the critical alert: FSDB file corrupted for resourceInternalId
  10. Configuring an End Point Operations Management Agent silent configuration script to populate the required fields automatically
  11. How to manually change the status of the cluster in vRealize Operations Manager 6.x
  12. vRealize Operations Manager 6.0 displays erroneous alarm: Virtual Machine is experiencing high number of receiver packets dropped
  13. Searching for any of the migrated objects in the Inventory Explorer displays two copies
  14. vSphere 6.x tags are not populated in vRealize Operations Manager 6.x
  15. Upgrading Multiple Endpoint Operation Management Agents Simultaneously from a Script for Versions 6.2 to 6.3 and 6.2.1 to 6.3
  16. vRealize Operations Manager 6.3 Sizing Guidelines
  17. Home Dashboard is missing or empty after upgrading to vRealize Operations Manager 6.3
  18. Selecting a subset of the vCenter Server inventory to monitor in VMware vRealize Operations Manager Standard 1.0.x or Manager 5.x
  19. Configure a certificate for use with vRealize Operations Manager
  20. Collections against one or more vCenter Server data centers fail

Top 20 vRealize Automation articles for September 2016

Top 20Here is our Top 20 vRealize Automation (vRA) articles list for September 2016. This list is ranked by the number of times a VMware Support Request was resolved by following the steps in a published Knowledge Base article.

  1. Deleting an endpoint in vRealize Automation fails with the error: This endpoint is being used by # compute resources and # storage paths and cannot be deleted
  2. Unable to add Active Directory users or groups to vCenter Server Appliance or vRealize Automation permissions
  3. Logging in to a tenant with verified administrator credentials or user credentials fails in VMware vRealize Automation 6.2.x
  4. Using JXplorer to update the LDAP string for an identity source for VMware vRealize Automation 6.0.x, 6.1.x
  5. Removing a virtual machine from Management in VMware vRealize Automation or VMware vCloud Automation
  6. Certificate troubleshooting, supportability, and trust requirements for vRealize Automation 6.2
  7. Connecting to a resource using the Remote Console (VMRC) option in VMware vRealize Automation 6.2.1 fails with the error: Cannot establish a remote console connection
  8. “Unable to connect on port” error when logging in to the vRealize Orchestrator
  9. Provisioning virtual machines using VMware vRealize Automation workflows fails to progress through the expected lifecycle
  10. Installing or configuring VMware vRealize Automation fails with the error: This implementation is not part of the Windows Platform FIPS validated cryptographic algorithms
  11. Migrating to a new SSO or recovering from a reinstallation of SSO in VMware vRealize Automation
  12. Configuring log rotation by file size in vRA appliance and vRO
  13. Various tasks fail after upgrading or migrating to VMware vRealize Automation 6.1.x or 6.2
  14. Signing VMware vRealize Automation certificates using an internal Microsoft CA signing authority
  15. Connecting the guest agent to IaaS on Windows 2012 fails with the error: Client certificate chain file not specified
  16. Setting the Kerberos token size for vRealize Automation deployments
  17. Changing the VMware vRealize Automation IaaS service account or updating the vRealize Automation IaaS service account password
  18. Logging in to the VMware vRealize Automation 6.2.x Appliance Management website fails with the error: Unable to authenticate user. Please try again
  19. Windows Session Authentication requirements for VMware vRealize Automation 6.2.x
  20. Troubleshooting 404 and 401 errors in VMware vRealize Automation 6.x by validating component configuration

Top 20 vCenter Server articles for September 2016

Top 20Here is our Top 20 vCenter articles list for September 2016. This list is ranked by the number of times a VMware Support Request was resolved by following the steps in a published Knowledge Base article.

  1. Licensing VMware vCenter Site Recovery Manager
  2. Resetting the VMware vCenter Server 5.x Inventory Service database
  3. Upgrading to vCenter Server 6.0 best practices
  4. vSphere handling of LUNs detected as snapshot LUNs
  5. How to repoint and re-register vCenter Server 5.1 / 5.5 and components
  6. ESXi 5.5 Update 3b and later hosts are not manageable after an upgrade
  7. Unmanaged workload is detected on datastore running SIOC
  8. vmware-dataservice-sca and vsphere-client status change from green to yellow
  9. How to register/add a VM to the Inventory in vCenter Server
  10. Downloading, licensing, and using VMware products
  11. Update sequence for vSphere 6.0 and its compatible VMware products
  12. Upgrading to vCenter Server 5.5 best practices
  13. Making a VMware feature request
  14. Enhanced vMotion Compatibility (EVC) processor support
  15. Update sequence for vSphere 5.5 and its compatible VMware products
  16. ESXi host disconnects intermittently when heartbeats are not received by vCenter Server
  17. Cannot remove or disable unwanted plug-ins from vCenter Server and vCenter Server Appliance
  18. Back up and restore vCenter Server Appliance/vCenter Server 6.0 vPostgres database
  19. vCenter Server 6.0 requirements for installation
  20. “Deprecated VMFS volume(s) found on the host” error in ESXi hosts