Sunday, November 13, 2011

Problem accessing CSV from passive Cluster Node

I recently had a perplexing problem where Cluster Shared Volumes in a Hyper-V cluster were not working correctly.  The volumes were only accessible from the node currently owning the volume.  Attempts to access the volumes from any of the other nodes resulted Windows Explorer hanging indefinitely.  Enabling maintenance or redirected mode made no difference.

Event ID 5120 was logged:  Cluster Shared Volume 'Volume1' ('Cluster Disk 1') is no longer available on this node because of 'STATUS_BAD_NETWORK_PATH(c00000be)'. All I/O will temporarily be queued until a path to the volume is re-established.
Event ID 5142 also occurred:  Cluster Shared Volume 'Volume1' ('Cluster Disk 1') is no longer accessible from this cluster node because of error 'ERROR_TIMEOUT(1460)'. Please troubleshoot this node's connectivity to the storage device and network connectivity.

I could ping all nodes over both the Production and Heartbeat network links, and I could access file shares from any node on any node.

The Problem
After much troubleshooting I realised I disabled both File and Print Sharing and Client for Microsoft Networks on the Heartbeat NIC on all nodes.  This is a best practice drummed into me since working on Microsoft Clustering when it was still code-named Wolfpack.

The Resolution
I enabled File and Print Sharing and Client for Microsoft Networks and immediately afterwards all my Cluster Shared Volumes started functioning as expected.

The Explanation
It’s documented in MS KB Article 2008795.  When accessing a CSV volume from a passive (non-coordinator) node, the disk I/O to the owning (coordinator) node is routed through a 'preferred' network adapter and requires SMB be enabled on that network adapter. For SMB connections to work on these network adapters, the aforementioned protocols must be enabled.  Ugh.

Saturday, November 12, 2011

Setting up a KMS server on Server 2008 R2

Today we’ll deal with setting up a Microsoft Key Management Server (KMS).  a KMS is used to activate Microsoft Volume Licensed products such as Windows 7, Office 2010 and Windows server 2008 R2, amongst others.

a KMS server activates a client for a period of 180 days.  The activated machine will communicate with the KMS every 7 days to renew it’s activation information.  It then resets the license counter back to 180 days if successful.  If not it attempts to background connect to the KMS every 2 hours.

If, after 180 days, the machine has not been able to contact the KMS it will go into the 30 day grace period and notify the user.  After that the machine will enter a reduced functionality mode until it can again connect to a KMS.

That was quite a mouthful – so let’s get down to setting up a KMS on a Windows 2008 R2 host.  In addition we’ll also set it up so that it can activate Office 2010 clients.

Setting up a KMS

  1. Activate Windows with a KMS key.  This will automatically configure the server as a KMS
  2. Download the Office 2010 KMS Host License Pack
  3. Enter your KMS host key when prompted (you will get this key from your Microsoft Volume Licensing website)
  4. Make sure to allow the Key Management Service through the Windows Firewall

Verify that KMS is published in DNS

nslookup -type=srv _vlmcs._tcp.<your DNS domain>

Checking the KMS status on your KMS

From an elevated command prompt, type SLMGR.vbs /dlv

Checking the license and activation status on a client

slmgr.vbs –dli

a KMS goes a significant way to easing administrative burden, so go ahead and set it up, it’s as easy-peasy!