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Monthly Archives: July 2009

KB Highlight: vSphere 4.0 HA cluster may not fail VMs over during host failure when ESX Host IP is configured with certain Class A IP address

We wanted to get the word out ASAP on another KB article today. This one
involves VMware High Availability (HA), and customers with this specific
configuration with vSphere 4 need to be aware of this bug.

In vSphere 4.0, HA does NOT failover VMs when an host failure occurs. When
the ESX host COS IP address in the cluster are configured with certain IP
address the node failure detection algorithm fails.

IP Range – HA Functionality

0.x.x.x – 2.x.x.x – Failover Works
3.x.x.x – 9.x.x.x – Failover DOES NOT
work
10.x.x.x – 25.x.x.x – Failover works
26.x.x.x – 99.x.x.x – Failover
DOES NOT work
100.x.x.x – 255.x.x.x – Failover works

The issue has been seen and reported on Class A IP Addresses. If your ESX
COS/Management IP Address is on an internal 10.x.x.x or 192.x.x or if you use an
Class B or Class C IP address, then you will not be affected by this issue.

Note that our team is working on a permanent solution to this issue.

Continue reading vSphere 4.0 HA cluster may not fail VMs over during host failure
when ESX Host IP is configured with certain Class A IP address
.

Storage Heavy Hitters

Our guys and gals that support Storage issues have identified the top 10 KB articles that get the most bang for the buck. These articles help resolve a lot of problems that customers run into. You might enjoy this list if you’ve ever run into issues with your storage arrays.

Watch this space in the coming days for more top ten lists. Coming up next, Installation KBs!

Article # Title
9453805 Resignaturing VMFS3 volumes from VMware Infrastructure Client
1004232 Cannot power on a virtual machine because the virtual disk cannot be opened
1002511 Recreating a missing VMDK (header) file
1008083 Configuring and troubleshooting basic Software iSCSI setup
1005009 Troubleshooting SCSI Reservation failures on Virtual Infrastructure 3.x and vSphere 4.x
1004771 Insight Manager may cause SCSI reservation conflicts
1006847 Committing snapshots from within the Service Console
1002310 Committing snapshots when there are no snapshot entries in the snapshot manager
1008130 VMware ESX and ESXi 3.5 U3 I/O failure on SAN LUN(s) and LUN queue is blocked indefinitely
6482648 VMFS Volume Can Be Erroneously Recognized as a Snapshot

KB Highlight: System does not clear RAID controller cache during shutdown

We recently discovered an issue that will only occur under very specific conditions. We felt that given the fact that there is a potential for data corruption, we would highlight this KB article here.

All of these conditions must be met to be affected:

  • Systems with ESX/ESXi 4.0 installed
  • The system is equipped with a RAID controller using one of these drivers:

    megaraid2
    megaraid_sas
    aacraid

  • RAID controller battery backup unit is completely discharged after a shutdown (48 hours or longer)
  • Local disks are attached to the affected HBA

Data corruption might occur because the RAID controller cache is not cleared while shutting down the server and will be lost when the battery backup is depleted.

Note that our team is working on a permanent solution to this issue.

Continue reading System does not clear RAID controller cache during shutdown

Top Ten System Management KBs

Based on the kind of questions and issues that come into support we’ve compiled a list of the top Knowledge Base articles for what we term ‘System Management’ issues. System Management is a difficult category to describe.  It generally revolves around vCenter and managing the resources it is in control of. DRS, HA, and VMotion come to mind as an example.

Here are some feature articles for this area:

Article #

Title

1003212

Enhanced VMotion Compatibility (EVC) processor support

1001596

Troubleshooting Adding an ESX Server Host to a VMware High Availability Cluster

1003490

Restarting the Management agents on an ESX Server

1009607

Pegasus (cimserver) memory leaks reported in ESX 3.5 Update 2 and later

1004382

After VirtualCenter 2.5 upgrade: Performance data is currently not available for this entity

1993

VMotion CPU Compatibility – Migrations Prevented Due to CPU Mismatch – How to Override Masks

1003691

Diagnosing a VMware High Availability cluster configuration failure

1003980

Troubleshooting transaction logs on a Microsoft SQL database server

749640

Cannot open Virtual Machine Console

1004667

Applying DRS settings to an ESX host generates an error

Got VMware Licensing Questions?

Ever since vSphere 4 came out we’ve had a surge in questions about the new licensing model. Did you know our Knowledge Base covers licensing as well as hard-core technical topics?

We tend to think of the Knowledge Base as a problem & fix resource, but we want to get the word out that it  also works as a general Q&A or FAQ resource.

Based on the kind of questions and issues that have come up we’ve compiled this list of the top Knowledge Base articles for Licensing.

Article # Title
1012581 Not for Resale (NFR) licenses
2011011 Super Users and Procurement Contacts in My VMware
1003304 Distinction between License Administrator (LA) and Support Administrator (SA)
1010690 vSphere 4.0 upgrade options
1005522 Registering a License Key
1010533 Downgrading vSphere 4.0 License to ESX 3.5 version
2014346 Missing licenses in your My VMware account
1010839 Licensing ESX 4.0, ESXi 4.0, and vCenter 4.0
1005526 Ensuring validity of Subscription Contracts to receive product upgrades
1009166 Uploading the License file to the License Server
2006831 How to view license keys in My VMware

Also not to be missed is our Communities Roundtable podcast #44 which covers licensing.

New Timekeeping KB article

linux-penguin-tux Today we published what someone here termed the Grand-daddy of all KB’s for Timekeeping issues with Linux guests. This is a frequently discussed topic in our forums and in the blogosphere in general, and the new KB is meant to guide you to the earliest resolution possible for any issues with clock speed in your Linux VMs.

Troubleshooting timekeeping issues in Linux guest operating systems (1011771)

Rumor has it that another, similar KB, about timekeeping issues in Windows guests is in the works.  Keep an eye on this space…

Top 20 Articles for June 2009

Here are our top 20 most used articles for the month of June.

Best practices for using and troubleshooting VMware Converter (1004588)

Consolidating snapshots (1007849)

Enhanced VMotion Compatibility (EVC) processor support (1003212)

Upgrading to ESX 4.0 and vCenter 4.0 best practices (1009039)

Increasing the amount of RAM assigned to the ESX Server service console (1003501)

Downloading, verifying, and installing Fusion (1005466)

Installing ESX 4.0 and vCenter 4.0 best practices (1009080)

Troubleshooting Adding an ESX Server Host to a VMware High Availability Cluster (1001596)

Restarting the Management agents on an ESX Server (1003490)

Virtual machine does not power on because of missing or locked files (10051)

Upgrading to ESX 3.5 and VirtualCenter 2.5 Best Practices (1003889)

Recreating a missing VMDK (header) file (1002511)

Powering off a virtual machine hosted on ESX host from the command line (1004340)

Troubleshooting startup issues or manually reinstalling Fusion (1003484)

Resignaturing VMFS3 volumes that are not snapshots (9453805)

Tech Support Mode for Emergency Support (1003677)

VMotion CPU Compatibility – Migrations Prevented Due to CPU Mismatch – How to Override Masks (1993)

After VirtualCenter 2.5 upgrade: Performance data is currently not available for this entity (1004382)

ESX lost heartbeat purple diagnostics screen error (1009525)

Verifying ESX virtual machine file integrity (1003743)