App Control Server: How to configure SQL Server MultiSubnetFailover Property

Products

• Carbon Black App Control (formerly Cb Protection)

Issue/Introduction

How to configure the SQL Server MultiSubnetFailover connection property for Always-On-Availability groups?

Environment

• App Control Server: All Supported Versions
• Microsoft SQL Server: All Supported Versions

Resolution

NOTE: App Control is designed to work with the Simple Recovery Model Full Recovery Model is required for Always On Availability Groups and Database Mirroring Simple Recovery Model is recommended in the App Control Operating Environment Requirements (OER) Full Recovery Model will increase the size of the Transaction Log and will result in additional considerations due to this growth. Review: Troubleshooting Transaction Log (das_log) Growth The following information is a best effort.  Design, implementation and maintenance of a SQL Server Always On Availability Group is outside the scope of Support.

1. If there is an App Control Agent installed on the application server, temporarily disable Tamper Protection.
2. Find and edit this file: C:\Program Files (x86)\Bit9\Parity Server\shepherd.dsn
3. Add the following line at the bottom of the document:

   MultiSubnetFailover=Yes

4. Find and edit the "ConnectionInfo" section of this file: C:\Program Files (x86)\Bit9\Parity Console\WebUI\PEAR\DB\sqlsrv.php
5. Add the line 'MultiSubnetFailover'=> 'yes' before the closing parenthesis, so it looks like:

   $connectionInfo =
   array(
   'DATABASE' => $dsn['database'] ? $dsn['database'] : null,
   'ReturnDatesAsStrings' => false, // Use custom formatting, bcs no way to configure built-in formatting
   'CharacterSet' => $this->_charset,
   'LoginTimeout' => $this->_logintimeout,
   'MultiSubnetFailover'=> 'yes'
   )

6. Restart the App Control services
7. Validate the content of sqlsrv.php after every Server upgrade as the file may get overwritten.