Desired State Configuration is the new configuration management platform built into Windows OS and is now available for Linux and Unix as an Open Source framework. This session at PowerShell Bangalore User Group demonstrated how DSC can be used to manage heterogeneous systems in a Data Center.

1. CROSS-PLATFORM CONFIGURATION
MANAGEMENT WITH
DESIRED STATE CONFIGURATION
Ravikanth C
Windows PowerShell MVP
PowerShellMagazine.com
@ravikanth

2. AGENDA
• DSC PRIMER
• DEMO

3. DSC PRIMER
• Address challenges in
– Continuous Delivery and Integration
– Configuration Management
• Management Platform
– Available for Windows and Linux/Unix
• Provides
– Language Extensions
– Resources
– PowerShell Cmdlets
• Declarative Style (DSL)
• Push and Pull configuration delivery

4. DSC PRIMER
What about these and
many others?

5. DSC PRIMER
• Configuration Management as an API
• Write your own tools to
– Author
– Stage
– Push
– Monitor
• Or use 3rd-party tools such as ScriptRock
GaurdRail and so on!

6. DSC PRIMER
• Configuration is stored at:
– Windows: C:WindowsSystem32Configuration
– Linux: /opt/omi-1.0.8/etc/dsc/configuration
• Current.mof – Present configuration (N)
• Backup.mof – Copy of Current.mof
• Pending.mof – Configuration changes
pending
• Previous.mof – N-1 configuration
• MetaConfig.mof – LCM configuration

7. DSC PRIMER
• DSC logs provide insight into
configuration changes and issues
• Windows: Event Logs
– Applications and Services
Logs/Microsoft/Windows/Desired State
Configuration
• Linux: /opt/omi-1.0.8/var/log

8. DSC IN ACTION & DSC API
Demo

9. DSC PRIMER
• Custom resource authoring is easy!
– Heard of Modules?
• For Windows OS
– Script Modules
– Binary Modules in C#
– MI Provider (native code)
• For Linux OS
– MI Provider

10. BACKUP

11. DECLARATIVE SYNTAX
Configuration ArchiveDemo {
Node SRV3-WS2012R2 {
Archive ArchiveDemo {
Path = "10.10.10.101BackupScripts.zip"
DestinationPath = "C:Scripts"
Ensure="Present"
}
}
}
ArchiveDemo
.PS1

12. DSC ARCHITECTURE

13. LCM API
CIM Method PowerShell Cmdlet
SendConfigurationApply Start-DscConfiguration
SendConfiguration -
ApplyConfiguration -
GetConfiguration Get-DscConfiguration
Rollback Restore-DscConfiguration
TestConfiguration Test-DscConfiguration
StopConfiguration -
SendMetaConfigurationApply Set-DscLocalConfigurationManager
GetMetaConfiguration Get-DscLocalConfigurationManager
PerformRequiredConfigurationChecks -

14. Custom Resources
• Three Functions
– Get-TargetResource
– Set-TargetResource
– Test-TargetResource
Start
Test-
TargetResource
Set-
TargetResource
False
End
True