“The RPC server is unavailable” while logging to Domain controller OR joining client machine to Domain Controller
There are many reasons to see this error,
I will discuss the issues that mostly make this happen

1] RPC service might be disabled.
Start the service through “services.msc”

2] RPC Dependencies services might be stopped
Start Dependencies services for RPC

3] You have client installed through OS image restore
Change the SID of Client machine using NewSID v4.10, its and utility provided on Microsoft site

4] Check the firewall between Domain controller and client machine for RPC port 135 must not be blocked
Unblock this RPC port for TCP

5] Check the SRV record for LDAP in DNS
Check for SRV record must be present [probably it is DC IP address]

6] Check for DNS configuration are proper and with out any error
Run “NetDiag /fix” to fix the issue on DNS server
To check the DNS zone for your new domain controller,
In Run type dnsmgmt.msc.
Expand Computer Name, expand Forward Lookup Zones, and then expand Domain.com
Confirm that the _msdcs, _sites, _tcp, and _udp folders exist.
After running “NETDIAG /FIX” command.
The most important test you will see is the first one, which is connectivity. This test will tell you if your domain controller is properly registered in DNS. If your tests are successful, you have a healthy domain controller. If this command shows “FAIL” result for any Diagnosis that is running on server then reboot Domain Controller and Re-Run this command
A typical successful output will start as follows:
Domain Controller Diagnosis

Performing initial setup:
Done gathering initial info.

Doing initial required tests

Testing server: Default-First-Site-NameAD01
Starting test: Connectivity
……………………. Domain.com passed test Connectivity

Tip “NETDIAG /FIX” command is present in 2003 support tools

Clustering in Windows 2003 Dedicated or Shared hosting is a means of providing High Availability to your applications and websites. Clustering is a group of machines acting as a single entity to provide resources and services to the network. In time of failure, a fail over will occur to a system in that group that will maintain availability of those resources to the network. You can be alerted to the failure, repair the system failure, and bring the system back online to participate as a provider of services once more. You learn about many forms of Windows clustering. Clustering in Windows 2003 hosting can allow for failover to other systems and it can also allow for load balancing between systems. Load balancing in Windows 2003 hosting is using a device, which can be a server or an appliance, to balance the load of traffic across multiple servers waiting to receive that traffic. The device sends incoming traffic based on an algorithm to the most underused machine or spreads the traffic out evenly among all machines that are on at the time. A good example of using this technology would be if you had a web site that received 2,000 hits per day. If, in the months of November and December, your hit count tripled, you might be unable to sustain that type of increased load. Your customers might experience time outs,
more…

Some times Configuring MSDTC and their error can ruin your Windows Cluster service and your time as well. You may get one of the following error when you failover the MSDTC service from one Dedicated node to another.

This would only happen if the Cluster services has been installed before installing and configuring MSDTC Service. Hence it is highly recommended that you first install and configure MSDTC and then configure the Windows Cluster Service.

Event ID: 4097
Description:
MS DTC started with the following settings: Security Configuration (OFF = 0 and ON = 1): Network Administration of Transactions = 1, Network Clients = 0, Distributed Transactions using Native MSDTC Protocol = 1, Transaction Internet Protocol (TIP) = 0, XA Transactions = 1.

OR

Event ID: 4395
Description:
MSDTC detected that MSDTC related information in the local registry is different from that in the shared cluster registry. Error Specifics: d:ntcomcom1xdtcsharedmtxclumtxclusetuphelper.cpp:541, CmdLine: C:WINNTSystem32msdtc.exe, Pid: 796
Data:
0000: 05 40 00 80 .@.?

OR

Event ID: 4384
Description:
MS DTC was unable to start because the installation was not configured to run on a cluster. Please run comclust.exe and restart MS DTC. Error Specifics: d:ntcomcom1xdtcsharedmtxclumtxclusetuphelper.cpp:668, CmdLine: C:WINNTSystem32msdtc.exe, Pid: 796

OR

Event ID : 7024
Source : Service Control Manager
Description: The MSDTC service terminated with service specific error 3221229584.

Initially you should try and run the command below and check if it solves the problem:

msdtc -resetlog

If that does not help then follow the fix below:

more…

This checklist helps you prepare for installation. It is very important to go through all of them else it make it very difficult to restart if either one of them is missed or not configured:

Software Requirements

•    Microsoft Windows Server 2003 Enterprise Edition or Windows Server 2003 Datacenter Edition installed on all dedicated servers in the cluster.
•    A name resolution method such as Domain Name System (DNS), DNS dynamic update protocol, Windows Internet Name Service (WINS), HOSTS, and so on.
•    An existing domain model.
•    All nodes must be members of the same domain.
•    A domain-level account that is a member of the local administrators group on each node. A dedicated account is recommended.

Hardware Requirements

•    Clustering hardware must be on the cluster service Hardware Compatibility List (HCL). To find the latest version of the cluster service HCL, go to the Windows Hardware Compatibility List at http://www.microsoft.com/hcl/, and then search for cluster. The entire solution must be certified on the HCL, not just the individual components.

more…

One can point your site to any designated IP address you want without changing the Name server of your Domain. Yes, you will be able to view/test your site on new server without changing the name servers as well as having trouble of using site Preview options in Control panel like Plesk. This option is also helpful in the case of some site that use .js script in their codes since those scripts don’t work in Plesk site preview option. Specially in case of sites that work on DotNetNuke [DNN].

So here we go:

On your local machine, [AND NOT THE SERVER]:
Goto START >> Run >> and Type:
notepad "C:WINDOWSsystem32driversetchosts"
And hit Enter

If you get file does not exist error then create hosts file in notepad “C:WINDOWSsystem32driversetc” folder.

At the end of the file you will have:

127.0.0.1 localhost

Just add your domain with the IP you want to point to, and it will look like, this will be also applicable if you have create a new hosts file:

127.0.0.1 localhost
192.168.1.52 mywebhostingblog.net
192.168.1.52 www.mywebhostingblog.net

Save the file and exit.

Now ping the domain on the computer you have made changes on and it will point to the IP address defined. You can now browse your site without the site preview and you will have to the content of the server you are moving to. Just remove the entries from the hosts file to point your domain back it was.

Wasn’t that Simple..!!!

The clustered nodes use a “heartbeat” signal to check whether each node is alive, at both the operating system level and the SQL Server level. At the operating system level, the nodes in the cluster are in constant communication, validating the health of all the nodes.

After installing a SQL Server failover cluster, the node hosting the SQL Server resource uses the Service Control Manager to check every 5 seconds whether the SQL Server service appears to be running. This “LooksAlive” check does not impact the performance of the system, but also does not do a thorough check; the check will succeed if the service appears to be running even though it might not be operational. Because the LooksAlive check does not do a thorough check, a deeper check must be done periodically; this “IsAlive” check runs every 60 seconds.

The IsAlive check runs a SELECT @@SERVERNAME Transact-SQL query against SQL Server to determine whether the server can respond to requests. Although a reply to the IsAlive query confirms that the SQL Server service is available for requests, it does not guarantee that all user databases are available, or that the user databases are operating within necessary performance/response-time requirements.

more…

Important prerequisite configuration for Windows cluster node before adding them to Cluster Service.

Prerequisite for Window cluster node

I will let you know the granular details to check on all node of cluster before adding
them to cluster services, these are minor but are very important to run Cluster Services

1] Naming convention for node should be predefined as once you name the server, It can not be changed.

more…

One of the ways by which Computers get affected by viruses is through USB Pen drives. Anti viruses are unable to detect them and even if they do, in most cases they are unable to delete the virus. Following are the precautions you can take when plugging USB Drive on your Computer.

Whenever you plug a USB drive in your system (which you think is infected by virus), do not open it -  Do not click ‘OK’ !
click on ‘Cancel’. Now open Command Prompt by typing ‘cmd‘ in run box.
Type dir /w/a and press enter.
Above command will display list of files in pen drive. Check in the list if the files are not

* Heap41a
* New Folder.exe
* Autorun.inf
* svchost.exe
* Ravmon.exe
* or any other exe file which may be suspicious.

If any of the above files are present in the list, then your USB drive is infected. To remove these files, type the following command in command prompt
attrib -r -a -s -h *.* and press enter.
This will remove from files  Read Only, Archive, System and Hidden attributes .

The files which you will now be looking on are the junk files (viruses) and can be deleted using  del command. Delete all those files which you find suspicious. To be on a safer side, just scan again your  USB Pen drive using a anti virus to check whether it is free of virus or not.

Difference between Hardware firewall and software firewall
Which firewall is best?

Well this question again generate a cross question.
What are your requirement?

If you need to protect your network through IP based regardless of Application using the port. Hardware firewalls has a strong and fast protection from most forms of attack coming from the outside world. Hardware firewall has a designed technique called packet filtering that examines the header of a packet to determine its source and destination addresses [IP’s].  This information is compared to set rules that determine whether the packet is to be forwarded or blocked
Now days a new technique called Stateful Packet Inspection (SPI) is used in firewall
That check the origin of packets that means it check whether the response is from internet, if yes whether it is the requested response for a machine from local network.
If yes the allow traffic
Bad thing is that, if, say, you get email containing WORD doc that has spyware/Macro hidden in it, which communicate to outer world when WORD file is opened/executed.
Your hardware firewall will allow communication to outer world and the requested incoming packets too, as the packet origin was from local network,
Resulting Machine infection

more…

Microsoft Windows Server 2003 does not install Collaboration Data Objects (CDO) for
NTS (CDONTS). Therefore, applications that use   do not function on a Windows
Server 2003-based computer.

Windows Server 2003 provides improved alternatives to CDONTS. To make CDONTS
functioning on a Windows Server 2003-based computer, use one of the following

solution:

more…