SQL Mirror Failover Steps

When To Use These Steps


When you have a planned server outage of the Principal Server. For example, if you are swapping or upgrading hardware or software component.

When Not To Use These Steps

You cannot and should not use these steps:

When the SQL Witness Server is down or unavailable.

Failure to do this will make the Imorgon product unavailable for the duration of the SQL Witness Server outage. This is because for the SQL Mirroring to work properly in the "high safety mode" at least 2 of the servers must be up from the mix of servers.  If you have lost the communications to both the Witness and the Principal server, you must contact Imorgon Support to break the SQL Mirroring manually and bring the Mirror server to a stand-alone SQL server. This is a very time-consuming (expensive) process to perform especially when we need to restore the mirroring when the original Principal server goes back into operation. Therefore please weigh this factor into doing this process.

What Will Happen If You Fail-Over


Things should operate normally. Imorgon workstations on the local network will operate continuously and if the "Virtual IP Address" is configured on the network, the modalities can send images to Imorgon server without requiring to change the DICOM destination.

Database backup in most cases will stop operating therefore you would want to make the time while fail-over to be relatively short, say no more than 48 hours. Your Primary server should almost always assume the Principal role as much as possible.

Preparation

NOTIFY US FIRST, Email is Fine, and Advise Your Own Users Too!

It is also a good idea to contact Imorgon support at iCare@imorgon.net that you plan to fail the systems over because the moment you do this, our monitoring system will alert the changes to us and if we did not hear from you we will start checking and even try to "fix" the problem by re-failing back or attempt to remotely restart computers.

While system and users should not experience a downtime, this is a complex system and there is a chance that some of the systems  (workstation and modalities) may not respond or operate properly. Therefore we recommend that you consider sending a quick note to all clinical users that you have a scheduled maintenance and that you do not expect a downtime, but possible problems should be reported to you right away.

The Steps

It is actually quite simple to do;

  • Remote Desktop connect (or go to the Server's Console Terminal) and log yourself in.
  • Open the SQL Server Management Studio from the Start Menu -> All Programs -> Microsoft SQL Server 2005 -> SQL Server Management Studio
  • When a log in dialog box comes up, select the Server Type of Database Engine, Server name should be the principal server name \ IMORGON and use the Authentication mode of Windows Authentication
  • On the left panel of the SQL Server Managment Studio, click and open the Databases folder. You should find ImorgonClinical and ImorgonConfig databases. Be sure that the databases are indicated as "(Principal, Synchronized). " If they do not say Synchronized, and instead say Mirror or Disconnected. Do not fail-over.
  • Now you are ready to fail-over ImorgonClinical Database
  • Right click over ImorgonClinical database
  • Select Tasks
  • Select Mirror...
  • Under the Database Properties dialog box, find the Failover button
  • Press it
  • The fail-over confirmation dialog box will appear. Press Yes.
  • Repeat the same steps for ImorgonConfig database.
The following pictures illustrate how it looks like on one of our test servers (vm-ucsf-01 is one of our test servers, not related to UCSF, sorry about the confusing pictures):























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