Citrix Server not accepting connections.

Description of the Problem: One server in the Citrix farm, suddenly stops accepting new ICA connections and RDP Connections.

Symptoms:

1) No new Citrix connections.

2) No new RDP connections.

3) Resource utilization on the server is normal.

4) Event ID 50 is observed in the event viewer with following error message

    Source: TermDD with the following error message:

"The RDP protocol component WD detected an error in the protocol stream and has disconnected the client."

5) Rebooting the server resolves the issue.

Cause:

1) Possibility is that the TS encryption certificate is out of sync or invalid.

2) Another possibility is that Rdpwd.sys (RDP WinStation driver) has crashed or got corrupted.

3) RDP TCP listener which represents the RDP-TCP protocol is down.

 

Solution:

Although the problem may resolve by restarting the server but you may try the following solution if you don’t want to restart sever.

 Without restarting the server.

A) Resetting the RDP-TCP and ICA-TCP listener.

1) Take the console session of the server (through RSA/ILO management card or through VCMS if it is a virtual server)

2) Login to the server with admin credentials.

3) I received this suggestion from Microsoft:

4) Launch TSCC.MSC and disable the RDP-TCP listener. (Right click on RDP-TCPà All Tasksà Disable)

5) Enable the RDP listener again.

6) Similarly do with ICA-TCP listener.

 

You may alternatively try the below two steps to recover from the situation. (Server restart needed)

B)  Deleting Registry settings

1.        Start Registry Editor.

2.        Locate and then click the following registry subkey:

“HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\TermService\Parameters”

 3.        Under this registry sub key, delete the following values:

 

*        Certificate

*        X509 Certificate

*        X509 Certificate ID

4.        Quit Registry Editor, and then restart the server.

 

C) Delete the RDP-TCP Listener.

1. Launch TSCC.MSC and delete the RDP-tcp listener.

2. Reboot.

3. Recreate the RDP-TCP listener. (http://technet.microsoft.com/en-us/library/cc771694.aspx)

SOX: IT Perspective

RDP Connection Drops after Sp1 Installation on Win2k8 R2 server

Issue: After installing Service Pack 1 of Windows 2008 R2, RDP connection is dropped after accepting username/pwd. Event viewer logs event id 7031 this "remote desktop services service terminated unexpectedly".

Solutions:

1)    Log on to the server console, download and install the following hotfixes.

Security Update for Windows Server 2008 R2 x64 Edition (KB2667402)

http://www.microsoft.com/download/en/details.aspx?id=29169

Security Update for Windows Server 2008 R2 x64 Edition (KB2621440)

http://www.microsoft.com/download/en/details.aspx?id=29116

Restart your server. In some cases simply installing KB2667402 solves it whereas in other both patch needs to be installed. Reapplying above hotfixes even if they have been reported as installed, fixes the issue.

2)    This problem appears to be directly related to the fact that SP1 is installed via a RDP session.

Replace rdpcorekmts.dll and rdpcode.dll with one copied from a working SP1 installation.

3)    Uninstall Sp1 and install it again through RDP console session.

Basics of Cloud Computing (An Interview)

Cloud Computing (Funny Video)

Performance Issues on Windows Server 2003

Symptoms    : Windows 2003 Server is frequently hanging and is dead slow when while you work on it. Also the following event is appearing repeatedly on it.

Event Type        : Error

Event Source    : DCOM
Event Category: None
Event ID             : 10010
Description       : The server {BA126AD1-2166-11D1-B1D0-00805FC1270E} did not register with

                              DCOM within the required timeout.

Solution     It appears as some MS patch might have changed the permissions on the following

                     registry key.
                     In order to resolve the problem, kindly verify the permissions and add the following
                     permissions if they are not aligned.

                        Registry Key: HKEY_CLASSES_ROOT\CLSID (and all child keys and values)

                   

                       

                          Permissions Added:  Authenticated users      : Read access 
                                                               Network Service             : Full control

Warning: The Windows registry is a mysterious place but if you're not comfortable editing it,
make sure to make a backup of your registry before you start tweaking.

The Green Footprints of Virtualization

Green IT refers to an attempt to reduce the impact of IT operations on the environment.

Green IT starts with manufacturers producing environmentally friendly products and encouraging IT departments to consider more friendly options like virtualization, power management and proper recycling habits. Green IT projects may have other benefits also however they are generally geared towards showing considerable enhancement in energy efficiency.

 

Virtualization can be a wonderful ally in our efforts to implement Green IT. Servers use energy and give off heat irrespective whether 100 % or 15% utilized. Virtualization is a technology designed to enable multiple application work-loads each having an independent computing environment to run on a single machine. This eliminates the approach of dedicating a single workload to a single server a practice that yields low utilization rates and allows virtualized servers to function near maximum capacity. 

With virtualization, you can consolidate the workloads currently running on a multiple underutilized servers onto fewer, more efficient servers and begin to realize possible savings and efficiencies that have been difficult to achieve previously. When virtualization is coupled with the green design of new server and storage hardware, offers an effective solution for keeping operational costs and energy demands in check.

The Last Resort

There are three engineers in a car; an electrical engineer,
a chemical engineer and a Microsoft engineer.
Suddenly the car just stops by the side of the road, and
the three engineers look at each other wondering what could
be wrong.
The electrical engineer suggests stripping down the
electronics of the car and trying to trace where a fault might
have occurred.
The chemical engineer, not knowing much about cars,
suggests that maybe the fuel is becoming emulsified and
getting blocked somewhere.
Then, the Microsoft engineer, not knowing much about
anything, comes up with a suggestion, “Why don’t we close
all the windows, get out, get back in, open the windows
again, and maybe it’ll work!?”

Annoying Citrix Program Neighborhood (PNA) agent PopUp

Problem Description: Whenever a user is logs in to Citrix, the below popup appears asking “What is the address of the server hosting your published resources?”

Solution: I propose two solutions

1) Delete the shortcut of the Citrix Program Neighborhood Agent from the Startup of the Workstation to get rid of this POPUP.

 Go to Start--> All Progs--> Startup-->Citrix XenApp --> Right Click and Delete

This will stop this annoying Popup but can be configured later if needed.

2) Create a PNA website along with the web interface. The default site name will be like as mentioned below. Configure this Url when the popup appears again

http://servername/Citrix/PNAgent/config.xml

You will get a new Pop up for the password prompt with user name and then you can see the application of this farm in your system tray on the right hand side bottom of your workstation. The Pop up will not appear again and you can login to the applications directly from the system tray rather than using the Web interface.

Problem in Trust Creation with Domain Controller on VM

Problem description: When you try to establish a trust from a domain controller running inside a VMware virtual machine, the trust is not established and is followed by the below error.

"The local security authority is unable to obtain an RPC connection to the Domain controller"

As per Microsoft it can be a DNS issue or RPC problem.

Resolution:  The origin of the problem is a component in a VMware Tools i.e. Shared Folders. The purpose of this component is to be able to share files between a management workstation and the virtual machine.

 Here is the resolution.

A)    Uninstall the Shared Folders component in your virtual machine (DC).

àGo to Add/Remove Programs à VMware Tools à click "change" à next à deselect "Shared Folders".

B)    Reboot the machine.

C)    Establish the trust.

Popular SysAdmin Quotes

“The problem with troubleshooting is that trouble shoots back.”  ~Author Unknown

“User is the word computer professionals use when they mean "idiot."  ~Dave Barry

“If a train station is where the train stops, what's a workstation?”  ~Author Unknown

“I haven't lost my mind; I have a tape back-up somewhere.”  ~Author Unknown

“What goes up must come down. Ask any system administrator.” ~Author Unknown

“In God we trust, all others we virus scan.”  ~Author Unknown

“Never meddle in the affairs of NT. It is slow to boot and quick to crash.” ~Stephen Harris

"What? No raise? No Backups, then!"    ~A Frustrated Sysadmin

“Treat your password like your toothbrush.  Don't let anybody else use it, and get a new one every six months.”  ~Clifford Stoll

“Rebooting is a wonder drug - it fixes almost everything.”  ~Garrett Hazel

"Like car accidents, most hardware problems are due to driver error."   ~Author Unknown

 "Unix is user-friendly. It's just very selective about who its friends are."  ~Author Unknown

“Difference between a virus and windows? Viruses rarely fail."  ~Author Unknown

New Features in VMware vSphere 5 at a Glance

     There are a lot new features that vSphere 5.0 brings and the list will be even longer if all API and backend changes are included. Listed below are some of the significant changes that vSphere 5 brings for its customers.

1)  Vsphere ESXi Convergence: VMware vSphere 5 is the first version of VMware vSphere built exclusively on ESXi™, the only hypervisor purpose-built for virtualization that runs independently from a general-purpose operating system with smallest footprint.

  

2)    VSphere Auto Deploy: Auto-Deploy will enable IT to automatically deploy servers “on the fly” and will be able to reduce the time it takes to deploy a datacenter with 40 servers from 20 hours to 10 minutes. Once the servers are up and running, Auto-Deploy will also automate the patching process, making it possible to instantly apply patches to many servers at once.

3)      New VM Hardware version: The new virtual machine format (Version 8) in vSphere 5 has several new features, including support for

è 3D graphics for Windows Aero

è  USB 3.0

4)      Compatibility: Continue to run virtual machines with the 4.x version of VMware Tools, and virtual hardware versions 4 and 7.

5)      Apple Product Support: Support for new guest operating systems including Mac OS X Server v10.6 (“Snow Leopard”).

6)      4X larger VMs : Virtual machines can now have up to 32 virtual CPUs and 1TB of RAM.

7)      New Licensing Model: vSphere 5 Licensing continues to be physical CPU based but now linked with pooled vRAM Entitlement instead of CPU cores and physical RAM.

8)      New command-line interface (ESXCLI): vSphere 5.0 introduces a new command line utility esxcli. Some of you will say that esxcli was already available before 5.0, and yes you are correct it was around however it has been completely revamped with new options and switches.

9)      ESXi Firewall:  A new service-oriented firewall with the capability to restrict access to services based on IP address and subnet mask.
                                                                

10)  VM Storage Profiles: Decrease the amount of administration required to properly deploy virtual machines by allowing for the creation of Profiles. These profiles typically list the requirements of storage and can be linked to a virtual machine.