Monday 27 July 2015

Best Practices for Virtualizing Domain Controllers

Virtual DC Best Practices


  1. DCs require VM High Availability
  2. Never pause, clone or snapshot a DC
  3. Not all backups are created equal
  4. Avoid clock drift
  5. Don't overprovision resources
  6. Ensure backups actually work
  7. Implement anti-affinity rules
  8. Separate client and administrative traffic
  9. Prioritise quick object restores
  10. Monitor storage performance
  11. Remain a bit physical
  12. Have a plan for disaster recovery


Reference documents

Monday 20 July 2015

Different digital certificate formats

Certificates can be exported in a number of different formats. This blog aims to clear up any confusion around what these formats are.

When exporting certificates in Windows the following options are available.

1. Export the private key:

  • .PFX format - Personal Information Exchange - PKCS #12
2. Do not export the private key:

  • .CER - DER encoded binary X.509 - use this for non-Windows devices that require the cert.
  • .CER - Base-64 encoded X.509 - use this for Windows devices that require the cert.
  • .P7B - Cryptographic Message Syntax Standard - PKCS #7 Certificates - use this when you want to export the issuing and root CA certs bundled with the server cert.


Tuesday 14 July 2015

How to migrate a XenApp database

Migrating the Database to a Different Version of the SQL Server

Migrating from one database version to the other might be necessary to move the data store to a more powerful server. The best method for migrating between versions of the database is to back up and restore the database using the utilities provided by the database software vendor.

To point a XenApp Server farm to a new database, complete the following steps:
Note: For the best performance, complete this procedure on the data collectors after all other servers are reconfigured.
  • Back up the existing farm database and restore the database to the new server.
  • Create a new DSN file that points to the restored database.
  • Run the dsmaint config command on the server with the new DSN file.
  • Stop and restart the IMA Service.
Important: Restarting the IMA Service instead of restarting the server might cause the SNMP service to initiate Dr. Watson, if SNMP is enabled. This error is benign.
  • Ensure that the server is pointing to the new data store by verifying the following registry setting:
HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\IMA\DataSourceName
  • If the IMA Service started successfully, copy the new DSN file to all servers in the farm.
  • Run the dsmaint config command to change the IMA Service configuration on all remaining servers in the farm.
  • Stop and restart the IMA Service on all servers in the farm.
Tip: You can execute Steps 6 through 8 on all the servers from a simple batch file placed in a central location.

Applicable products

  • XenApp 6.5 for Windows Server 2008 R2
  • XenApp 6.0 for Windows Server 2008 R2
  • XenApp 5.0 for Windows Server 2008

Further reading


Citrix Receiver customizations

External links




Citrix Receiver apps open in the background - fixed

Issue

Citrix Receiver 4.x is installed on 64-bit Windows 8.x. Whenever an application is launched from Receiver by clicking on it, it opens in the background (behind the Receiver window). This may cause users to think that nothing is happening and prompt them to click the icon again.

Resolution

The following registry keys need to be applied to the client-side computer, But first, log out of Receiver, close and exit the application by right-clicking on the icon in the system tray / notification area and selecting Exit.

This can also be accomplished by copying the below text, pasting into notepad and saving as a REG file (e.g. "CitrixReceiverRegFix.reg") or by applying through Group Policy.

Note that the below keys are for 64-bit Windows clients. For 32-bit Windows clients, simply remove the "Wow6432Node" key from the entries below:


Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\ICA Client]
"ForegroundProgressBar"=dword:00000001
"NotificationDelay"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\ICA Client\Engine\Configuration\Advanced\Modules\WFClient]
"TWISeamlessFlag"="1"

[HKEY_CURRENT_USER\Control Panel\Desktop]
"ForegroundLockTimeout"=dword:00000000

[HKEY_USERS\.DEFAULT\Control Panel\Desktop]
"ForegroundLockTimeout"=dword:00000000