Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

Mounting a Passive copy of a database in a DAG if the Active copy fails

Posted on 2013-01-30
2
1,047 Views
Last Modified: 2013-02-01
I have been searching around for a documented procedure for preparing a passive copy of a database in a DAG when the Active database fails. When all is well, its easy to activate a passive copy  but what happens if the server crashes or the database unexpectedly becomes corrupt and dismounts.Most likely the Passive copy will failed/suspended or failed /resynchronizing state and may not mount if all the logs have not been copied over to play back.
0
Comment
Question by:osiexchange
2 Comments
 
LVL 63

Assisted Solution

by:Simon Butler (Sembee)
Simon Butler (Sembee) earned 125 total points
ID: 38839819
As long as the databases are healthy, and the FSW is available then it should just mount. If you are going in to a suspended/unmounted state then something is wrong with your DAG operation. Many times I have just rebooted the active server and the passive takes over without any interaction from me.

Simon.
0
 
LVL 15

Accepted Solution

by:
GreatVargas earned 125 total points
ID: 38840148
As Sembee said the behavior is to automatically get the passive copy mounted.. meaning that server will take over the database copy if the server were it's mounted fails.. that's the expected behavior  on a healthy DAG.

also probably you should be aware of two things:

1- Lagges copies
some customers like to have lagged copies to prevent a corruption to replicate over to several database copies (this is a huge discussion topic). just to let you know that if you have a lagged copy of 1 day for example.. meaning that the logs are replicated from the active copy to the lagged copy 1 day after being created.. you need that 1 day of logs to replicate before the other server takes over.. so the bottom line is, dont use lagged copies unless you're under a scenario were you really need to (i.e low bandwith links between the sites)

2- Database Activation Policy
you can prevent database copies from being activated automatically by changing the activation policy at the mailbox server level
http://technet.microsoft.com/en-us/library/dd298046(v=exchg.141).aspx

hope that helps
0

Featured Post

Optimizing Cloud Backup for Low Bandwidth

With cloud storage prices going down a growing number of SMBs start to use it for backup storage. Unfortunately, business data volume rarely fits the average Internet speed. This article provides an overview of main Internet speed challenges and reveals backup best practices.

Question has a verified solution.

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

Learn to move / copy / export exchange contacts to iPhone without using any software. Also see the issues in configuration of exchange with iPhone to migrate contacts.
Scam emails are a huge burden for many businesses. Spotting one is not always easy. Follow our tips to identify if an email you receive is a scam.
In this video we show how to create a Shared Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Sha…
In this Micro Video tutorial you will learn the basics about Database Availability Groups and How to configure one using a live Exchange Server Environment. The video tutorial explains the basics of the Exchange server Database Availability grou…

839 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