What windows cluster programming is all about

Extending Cluster Administrator in Windows Server 2003

2005-06-22T16:55:00.000-05:00

A very good article about writing your own Cluster Resource Extension DLLs.

Debugging: Root Out Elusive Production Bugs with These Effective Techniques -- MSDN Magazine, July 2005

2005-06-14T08:48:00.000-05:00

A very good article about WinDbg. I ahve been searching for some good User mode WinDbg articles for a long time without any success. This article is exactly what I wanted.

Google to have 3D Maps

2005-06-09T09:03:00.000-05:00

I dont know how this is going to help if you are using it on a desktop. If I can see this map on my SmartPhone, that would be really something!!

Back in the USA

2005-06-08T10:07:00.000-05:00

I am back after a hectic India trip.

I hope to update this blog frequently from now on.

C# code snippet for sending email using .NET

2005-05-02T14:56:00.000-05:00

Forget MAPI, SMTP and POP3 protocols and the complexity they bring with them. .NET wraps all those functionality and makes programming fun again.

using System.Web.Mail;
.
.

SmtpMail.SmtpServer = "your-smtp-server.com";

MailMessage mail = new MailMessage();

mail.From = "from@email.com";
mail.To = "recepient@email.com";
mail.Subject = "Mail Subject";
mail.Body = "Sending a mail using .NET is only few lines of code.";
mail.BodyFormat = MailFormat.Html;

//Optional Attachment

MailAttachment att = new MailAttachment("c:\\temp\\attachment.doc");
mail.Attachments.Add(att);

//Your mail is on the way
SmtpMail.Send(mail);

Travelling to Bangalore next week.

2005-05-02T14:46:00.000-05:00

I will be travelling to Bangalore for a long deserved vacation. I will be vacationing in Bangalore for 3 weeks. I will keep this blog updated with my take on Bangalore. I will also be posting some pictures from by Bangalore trip.

Well, its not really a vacation as Bangalore my city of birth. But being away from Bangalore for many years, it sure feels like a vacation.

Florin Lazar's WebLog : Using Windows XP SP2, Windows Server 2003 SP1 and MSDTC on Clusters

2005-04-27T06:26:00.000-05:00

I would like to experiment this when I get some spare time
Florin Lazar's WebLog : Using Windows XP SP2, Windows Server 2003 SP1 and MSDTC on Clusters

How cluster reserves a disk and brings a disk online

2005-04-24T07:32:00.000-05:00

A behind the scenes look at how a "Physical Disk"resource works in a Cluste Environment
How cluster reserves a disk and brings a disk online

'Seinfeld' inspiration offers soup line - Apr. 22, 2005

2005-04-22T13:01:00.000-05:00

Interesting. No soup for u!!
'Seinfeld' inspiration offers soup line - Apr. 22, 2005

How to set description for a Cluster Resource

2005-04-20T17:18:00.000-05:00

It is easy to set the Description field of a Cluster resource from code.

For example this function sets the Description of a "Cluster Name" resource type. The same technique can be used to set the Description for any custom resources that you write.


void
SetResourceDescription()
{
 typedef struct
 {
    LPCWSTR Description;
 }  SDescription;

 SDescription temp;
 temp.Description = L"My Custom Description";

 RESUTIL_PROPERTY_ITEM
 propList[] = {
    { L"Description",
       NULL, CLUSPROP_FORMAT_SZ,
      0, 0, 0, 0,
      FIELD_OFFSET(SDescription, Description) },
    { 0 }
 };
 DWORD dwStatus = ERROR_SUCCESS;

 wchar_t pBuffer[1024];
 DWORD bufferSize = 1024;
 DWORD bytesReturned, bytesRequired;
 dwStatus = ResUtilPropertyListFromParameterBlock
                           ((PRESUTIL_PROPERTY_ITEM)&propList,
                            (PVOID*)&pBuffer,
                            &bufferSize,
                            (LPBYTE)&temp,
                            &bytesReturned,
                            &bytesRequired);

 if(ERROR_SUCCESS == dwStatus)
 {
    dwStatus = ClusterResourceControl(
                    OpenClusterResource(OpenCluster(NULL),
         L"Cluster Name"),
                      NULL,
                      CLUSCTL_RESOURCE_SET_COMMON_PROPERTIES,
                      pBuffer,
                      bytesReturned,
                      NULL,
                      0,
                      NULL);

 }
}

This is how it would look in Cluster Administrator

Server Clusters: Majority Node Sets (a.k.a. Quorum of Nodes)

2005-04-20T11:17:00.000-05:00

A very good article on how majority node sets work in Windows 2003 Clustering.
Server Clusters: Majority Node Sets (a.k.a. Quorum of Nodes)

Added trackback from Haloscan. Looks pretty cool

2005-04-19T16:51:00.000-05:00

Haloscan commenting and trackback have been added to this blog.

.NET Rocks

2005-04-18T16:57:00.000-05:00

Recently i started listening to .NET ROCKS! an internet podcast for .NET and Microsoft developers. I must admit that I am blown away by it. Good bye NPR and Hello Podcasts!!.

I also listen to the WGBH Morning Editions. I am now hooked to podcasting. I am looking forward to Podcasts from Microsoft itself. Granted they have video feeds for .NET Show, MSDN TV and Channel 9. But I would like to see something which i can listen on my commute to work.

BTW, check out iPodder for automatic sync to iPods.

Uninstall Cluster Services in Windows Server 2003

2005-04-18T16:49:00.000-05:00

Have you noticed that Cluster Services are installed by default in Windows Server 2003? The side effect of this is that the Cluster Services cannot be uninstalled as in Windows Server 2000. This could create a problem specially in a development environment where the Cluster Service fails to start up and you cannot reinstall the service.

The way out of this is to clean up one node at a time from command line

>cluster node nodename /forcecleanup

Clean the node that caused the Cluster service to crash and start the cluster service on the other nodes. If you are lucky the Cluster will start up and you can add the cleaned node back to cluster through the Cluster Administrator. Otherwise repeat the same steps after cleaning up
other nodes of the cluster.

If you can get the cluster up with at least one node then you can add back the nodes you cleaned up to the cluster. If not, you will have to rebuild the cluster.

Hopefully you will never have to do this in a production environment.

Install Cluster Services using Local Quorum

2005-04-18T14:34:00.000-05:00

Windows 2000 Servers do not support Majority Node Set for a quorum resource. Majority Node Set is a new feature in Windows Server 2003.

In Windows Server 2000, you need a shared SCSI physical disk to install and configure a cluster. There is an excellent MSDN article "Step-by-Step Guide to Installing Cluster Service" which explain in detail about installing cluster service on Windows Server 2000.

However if you do not have a physical disk connected to your servers and would like to experiment with Clusters you could use a "Local Quorum" resource type as quorum. To achieve this, after the install of the Cluster components is complete, close the Cluster Configuration wizard and open the command window.
Go to %SystemRoot%\Cluster and start the Cluster Configuration wizard from the command line as

>cluscfg -localquorum

This will create a "Local Quorum" resource and hence will allow the cluster to be formed. Note that this is not a good idea for production environment and should be used for testing purposes only.

About me and what this blog is all about.

2005-04-18T10:44:00.000-05:00

have been doing Windows programming in C++ for the past ten years. I have worked on a lot of interesting projects in the past ten years. I have also worked a lot on ATL COM in the past five to six years.

Recently I got introduced to Windows Clustering technologies. It is an very interesting product and I have had a chance to work with it developing new resources. When I Google "windows cluster" I find a lot of information about configuration/install of Clusters and very very little (if any) on developing new resource types. The only source of information I could find for developing resource types was the inadequate MSDN documentation.

I will try to document my journey through this experience of developing new resources and also some general tips about Clustering that I find useful and interesting.