[Last Call] Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

SQL Mirroring with automated failover?

Posted on 2008-11-20
7
Medium Priority
?
982 Views
Last Modified: 2012-05-05
Dear Sir,

I have already configured an SQL mirroring for my Database with 3 physical servers:
1- Principal  (Identical Hardware) - Windows Server 2003 Standard SP2 - SQL 2005 SP2
2- Mirror        (Identical Hardware) - Windows Server 2003 Standard SP2 - SQL 2005 SP2
3- Witness    Windows Server 2003 R2 Standard SP2 - SQL 2005 SP2

Here is more details about my application:

- I have SUN thin clients (SUN Ray) taking windows session from 3 Windows 2003 TS 64 Bit Entreprise Edition, configured as NLB and running a Windows application. These servers are joined to a domain.
And my 3 SQL servers are joined also to the same domain.
So The Windows application running on my 3 Terminal Servers connected to my SQL Principal Server.

I configured my principal SQL Server as mirroring using the High Availability mode to implement an automated failover for my database.

But the problem is, when I am shutting down my principal SQL server to test the fail over, my application crashed and gives error message on users clients, however the auto failover was working fine, the mirrored SQL became principal and the principal SQL became mirrored.
My application using a default connection to my principal SQL Server IP.
Please find the attached file for more information.

Please any help?

Thank you in advance,
SQL-Configuration.jpg
SQL-Mirroring-Report.doc
0
Comment
Question by:ISC-IT-Admin
  • 4
  • 3
7 Comments
 
LVL 51

Expert Comment

by:Ted Bouskill
ID: 23019656
Mirroring failover is a manual process.  If you want automatic failover you have to use clustering.  Sorry
0
 
LVL 1

Author Comment

by:ISC-IT-Admin
ID: 23019889
Hell Tedbilly,

So why there is a witness server in mirroring, ( the configuration is High Saftey with automatic failover) Synchronous??
How can I fix my Issue?

Thank you,
0
 
LVL 51

Accepted Solution

by:
Ted Bouskill earned 1500 total points
ID: 23022694
It will only work if the client supports flipping from SQLInstanceA to SQLInstanceB.  Clustering doesn't have that requirement.  In a cluster there is always a SQLInstance that switches between servers.

Also mirroring is per database.  If you have an application that uses multiple databases mirroring failover is consistent which can cause problems.  For example, Sharepoint 2007 uses multiple databases and does not support mirroring.

http://www.microsoft.com/technet/prodtechnol/sql/2005/dbmirror.mspx#E6KAG

If you own the client application and control the SQL connection string you can do a client side redirect like so:
"Data Source=A;Failover Partner=B;Initial Catalog=AdventureWorks;Integrated Security=True;"

If your clients can't automatically redirect to a new SQL instance you need a cluster.
0
Get your Conversational Ransomware Defense e‑book

This e-book gives you an insight into the ransomware threat and reviews the fundamentals of top-notch ransomware preparedness and recovery. To help you protect yourself and your organization. The initial infection may be inevitable, so the best protection is to be fully prepared.

 
LVL 1

Author Comment

by:ISC-IT-Admin
ID: 23023758
Thank you tedbilly,

Please could you give me a detailed document with screen shot if avaialabe on how to configure a cluster for my SQL database?
I have already 2 indentical physical servers with SQL 2005 SP2. But Windows Server 2003 Standard Edition installed.


Thank you for your help,

0
 
LVL 51

Expert Comment

by:Ted Bouskill
ID: 23023785
This link has all the information you need:

http://www.microsoft.com/windowsserver2003/technologies/clustering/resources.mspx

Clustering costs more money and is far more difficult to set up.  Ultimately you have to decide how important it is to have 100% automatic failover.
0
 
LVL 1

Author Comment

by:ISC-IT-Admin
ID: 23023859
Ouf I understand.
Thank you a lot tedbilly,

Honestly, I am thinking about using mirroring auto failover because we own our client application with SQL connection.
So, as you told me how can we redirect the DB if the principal server goes down?
"Data Source=A;Failover Partner=B;Initial Catalog=AdventureWorks;Integrated Security=True;"

I need some more information regarding the auto redirecting.
Bcz I already configured my SQL DB as mirroring using 3 physcial servers with Witness (High Availability).
But still only this issue when the Main SQL goes down the application crashed, bcz the default connection doesn't exist anymore to the prinicipal server.

Thank you for your help.




0
 
LVL 51

Expert Comment

by:Ted Bouskill
ID: 23023925
0

Featured Post

Get quick recovery of individual SharePoint items

Free tool – Veeam Explorer for Microsoft SharePoint, enables fast, easy restores of SharePoint sites, documents, libraries and lists — all with no agents to manage and no additional licenses to buy.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

When writing XML code a very difficult part is when we like to remove all the elements or attributes from the XML that have no data. I would like to share a set of recursive MSSQL stored procedures that I have made to remove those elements from …
In this article I will describe the Copy Database Wizard method as one possible migration process and I will add the extra tasks needed for an upgrade when and where is applied so it will cover all.
Loops Section Overview
When cloud platforms entered the scene, users and companies jumped on board to take advantage of the many benefits, like the ability to work and connect with company information from various locations. What many didn't foresee was the increased risk…

834 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question