Upgrade Error - Valid Database compatibility level and successful connection rule

Recently when I was trying to upgrade an SQL Server 2008 R2 instance to SQL Server 2012, I was presented with an error during the upgrade rules validation.
The error message was, "The report server database is not a supported compatibility level or a connection cannot be established."

When I checked the reporting server databases, the databases had the right compatibility level.

Then I found that the SQL Server Name defined in the Reporting services configuration manager was not existing. This caused the validation rule to fail.

After changing the SQL Server Name to right server name, all the validations passed and it let me upgrade the SQL Server Instance. 

Change SSAS Deployment mode from multidimensional to tabular mode without reinstalling Analysis Services

It so happens that sometimes minds change easily and things needs to be done without reinstalling.
One such case is changing the Deployment mode of SSAS from multidimensional to tabular mode in SQL Server 2012.
To change the deployment mode

• Backup the multidimensional Analysis services databases on the instance (if any)
• Detach the multidimensional Analysis services databases from the instance (if any). These databases will not be usable in tabular mode
• Navigate to the path "<Install Location>:\Program Files\Microsoft SQL Server\MSAS11.MSSQLSERVER\OLAP\Config" and backup the file "msmdsrv.ini"
• Open the file "msmdsrv.ini" and change the value of DeploymentMode to 2.
  0 - Multidimensional
  1 - SharePoint
  2 - Tabular
  
• Re-Start the SQL Server Analysis services 

SSAS multidimensional mode - Before Change

SSAS tabular mode - After Change

Error while installing SQL Server 2012 - Access to the path 'C:\Program Files\Microsoft SQL Server\110\License Terms\SQLServerDenaliCTP_License_EVAL_1033.rtf' is denied.

When installing SQL Server 2012 you might run into an error which says "Access to the path 'C:\Program Files\Microsoft SQL Server\110\License Terms\SQLServerDenaliCTP_License_EVAL_1033.rtf' is denied."

To workaround this error, browse to the path "C:\Program Files\Microsoft SQL Server\110\License Terms\" and change the property of file "SQLServerDenaliCTP_License_EVAL_1033.rtf" to remove "Read-Only" and then click "Retry" and the installation will continue.

When was my database last taken Offline or Online

Here is a T-SQL script which tells when and who took the database offline or online recently.
This script utilizes the default trace and if the trace is reset after the database went offline or online then you have change the trace file path and name in the script.

DECLARE  @DBNAME nvarchar(100)
  ,@FileName nvarchar(max)
  ,@spid int
  ,@LogDate Datetime
  ,@Status nvarchar(10)
  
SET @DBNAME = 'AdventureWorks2008R2' -- Change DB Name
SET @Status = 'OFFLINE' --[OFFLINE or ONLINE]
SELECT @FileName=[path] FROM sys.traces WHERE is_default=1

DECLARE @ErrorLogTable table (Logdate datetime, ProcessInfo nvarchar(10), [Text] nvarchar(max))

INSERT INTO @ErrorLogTable
EXEC xp_readerrorlog 0,1, @Status, @DBNAME, NULL, NULL, 'desc'

SELECT TOP 1 @spid=cast(SUBSTRING(ProcessInfo,5,5) AS int)
   ,@LogDate=cast(Logdate AS nvarchar) 
FROM @ErrorLogTable

SELECT DatabaseID, DatabaseName, HostName, ApplicationName, LoginName, StartTime
FROM sys.fn_trace_gettable( @FileName, DEFAULT )
WHERE spid=@spid and DatabaseName=@DBNAME and CAST(StartTime AS nvarchar)=@LogDate

SQL Server Replication - Configuring Peer-to-Peer Replication

The first step in configuring the Peer-to-Peer replication is to configure the distribution on all the involved SQL Server instances.
To configure the distributor, follow the steps posted here.
Once the distributor is configured on all the involved instances, we need to configure the transactional publication.
To configure the publisher, follow the steps posted here.
Once the publisher is configured, we need to enable the peer-to-peer replication for this publisher.