The document discusses migrating .NET applications to Cloud Foundry to improve efficiency. It describes building a shared environment for .NET apps but notes limitations like lack of elasticity. Cloud Foundry provides true runtime elasticity and lifecycle management through BOSH. There are two paths for .NET Cloud Foundry parity: BOSH Windows for legacy apps and .NET Core on Linux. Considerations for migration include making apps cloud-ready and leveraging managed services.

1. Migrating .NET apps to
Cloud Foundry
A Strategy For Enterprises

2. Your Presenter
● Nicholas Grabowski
● Managing Principal at Charles Schwab & Co.
○ Application Architecture Team
○ R&D Team
● Engineering Leader, Executive, Technologist, Architect
● Primary industries: Financial Services and Retail
● Primary focus: Making technology more efficient
August 4th, 2016

3. Audience
● Architects, Engineering Leaders, Data Center Ops
● .NET Shops or those with lots of .NET apps
● Have 100s of apps or microservices
● Enterprises with lots of software
Assumptions:
● You are somewhat familiar with Cloud Foundry

4. A little about our situation & goals.
Situation:
● 100s of .NET, Java, Mainframe, Legacy C,
C++ applications
● Highly regulated environment
● Security is paramount
● Prefer CAPEX over OPEX
● Availability and reliability critical
● Brand conscious, risk averse
Goals:
● Bend cost curve of infrastructure, licensing
● Reduce complexity of deployments
● Leverage available capacity (app density)
● Adhere to our own standards
● Improve security posture
● Improve availability and reliability SLAs
● Improve agile, self service, devops maturity
● Prepare for public cloud
● Do “More, Better, Faster, Cheaper”

5. Shared Environments - What we built
We started before there were PAAS solutions.
We could see value in consolidating many apps to a
cluster of VMs rather than 1 app per cluster.
So we built Java and .NET “Shared Environments”.
Our .NET env looks like:
● IIS on Windows Server 2008
● Standard server configuration
● Standard networking and firewall rules
● Standard IIS configuration
● All apps deployed to all nodes
Shared Environment DC 2
Shared Environment DC 1
Node1
App1 App2 Appn...
Node2
App1 App2 Appn...
NodeN
App1 App2 Appn...
...
Firewall/Loadbalancer
Client
Apps

6. Shared Environments - Made Some Progress
Goals “kind of” accomplished:
● Bend cost curve of infrastructure, licensing
● Reduce complexity of deployments
● Leverage available capacity (app density)
● Adhere to our own standards.
● Improve security posture
● Improve availability and reliability SLAs
● Improve agile, self service, devops maturity
● Prepare for public cloud
● Do more: “More, Better, Faster, Cheaper”● Avoided 1000s of VMs
● Avoided 1000s of licenses
● Avoided ops team expansion

7. Shared Environment DC 2
Shared Environment DC 1
Shared Environments - But Not Enough
Shared Envs gave us a much greater app density
per machine, provided isolation characteristics,
reduced heterogeneity, and improved CD
integration.
But it had limitations:
● No elasticity
● No life cycle management, Pets not cattle
● Containerization is limited
● Security features are limited
Pet1
App1 App2 Appn...
Pet2
App1 App2 Appn...
PetN
App1 App2 Appn...
...
Firewall/LoadBalancer
Client
Apps
Noisy Neighbor App1 failure impacts other apps

8. Enter Cloud Foundry
● True runtime elasticity
● Lifecycle Management (no more pets)
● Better containerization
● Improved security posture
Goals could be accomplished for Java
● Bend cost curve of infrastructure, licensing
● Reduce complexity of deployments
● Leverage available capacity (app density)
● Adhere to our own standards
● Improve security posture
● Improve availability and reliability SLAs
● Improve agile, self service, devops maturity
● Prepare for public cloud
● Do “More, Better, Faster, Cheaper”

9. Enter Cloud Foundry - BOSH is the Key
“BOSH is a project that unifies release engineering,
deployment, and lifecycle management of small and
large-scale cloud software. BOSH can provision and deploy
software over hundreds of VMs. It also performs monitoring,
failure recovery, and software updates with zero-to-minimal
downtime.” - bosh.io
Bosh, Stem cells, Go router enable:
● Elasticity
● Life cycle management, Cattle not pets
● Containerization is robust
● Security features are robust
Cloud Foundry DC 2
Cloud Foundry DC 1
Node1
App1 App2 Appn...
Node2
App2
NodeN
App1 App3
...
Router
Client
Apps
BOSH
App4
App5

10. .NET CF parity - 2 paths
BOSH Windows
● Life cycle of fully managed by CF
● Will run .NET 4.5
● 100s of Billions (Trillions?) of lines of legacy
code need a home
● Windows only shops need a solution
.NET Core on Linux
● Only .NET Core
● Auditors less concerned with linux
● Limits complexity of CF
● Reduces legacy (Active Directory, IIS, etc.)
● .NET on par with other open source
11/2015 - Windows workloads deployable to CF, but parity not achieved… what is
needed?

11. Migration Considerations
BOSH Windows:
● Consider 12 factor - i.e. cloud readiness
● Remove dependencies on NFS
● Logging will need to change
● Make sure apps are node unaware
● Leverage off host session management
● Externalize environment configuration
● Avoid joining an AD Domain
● Avoid administering nodes directly
.NET Core Linux:
…. All of “BOSH WIndows” +
● .NET Core is more like a port than upgrade
● MSFT infamous for Betas as GAs
● .NET Core support model different
● Replace IIS with Kestrel or Web Listeners.
● Look to integrate CF Managed Services like
○ Messaging (e.g. Rabbit MQ)
○ Session Management (e.g. Redis)
The risk averse should consider a Shared Env first. For the rest of us...

12. Thanks
Contact me at:
● nicholas.grabowski@schwab.com
● ng@ngsoft.org
● http://www.linkedin.com/in/ngsoft
Shameless Recruiting Plug:
● Are you a solutions or enterprise architect?
● Are you a developer who wants to be an architect?
● Interested in working with the latest technology?
If so, Charles Schwab has an endless supply of multi million
dollar challenges?
http://jobs.schwab.com/