In the report, mechanisms of communication between microservices within a cluster were addressed, as well as multi-tier versioning, from the application level up to services and configurations. Also, pros and cons of Stateful Services were discussed and state management in Stateful Services reviewed. There were shared practical tips on minimizing effort while using Microsoft Service Fabric on a daily basis. This presentation by Andriy Gnennyy, Senior Consultant, leader Cloud-practice at GlobalLogic Kharkiv, was delivered at GlobalLogic Kharkiv MS TechTalk #3 on April 24, 2018.

1. 1
Microservices on Microsoft Service Fabric
Andriy Gnennyy
Senior Consultant, Delivery/Cloud Practice
April 24, 2018

2. 2

3. 3
Agenda
1. Overview
2. Connections & Communications
3. State management
4. Versioning
5. Continuous deployment

4. 44
Microservices: Azure options

5. 5
Options for Microservices
Azure Container Service (AKS)
Azure Functions Azure Service Fabric Azure App Service (Web Apps)
Azure Cloud Services
Azure Container Instances

6. 6
Best option for complex .Net (Core) Microservices
Azure Service Fabric
• Secure, flexible and robust
• Ready to scale & to handle extra complexity
• Incorporates state management
• Cross-platform engine
• Becomes open source (work in progress)
• And more...

7. 7
Service Fabric architecture

8. 88
Connections & Communications

9. 9
Some Systems are Simple...

10. 10
How Internal Discovery Works
… also there is optional support for internal DNS discovery

11. 11
Reverse Proxy Role
N nodes x M services + Dynamic Ports + Port Sharing + Partitions + … = Issue???

12. 12
Is HTTP the Only Option?
Consider Service Remoting. … and use V2
• Integrated service discovery
• Lightweight & fast
• Easy to configure
• Supports custom serialization
• Security based on certificates
ServiceA
IServiceA
ServiceAProxyServiceB

13. 1313
State management

14. 14
Traditional Approach: Tiers and Databases

15. 15
Let Service Own its Data: “Singleton” - Part 1
Register()
Registration
Service
(stateless)
Select Count
Add New Row
DatabaseGetCount()

16. 16
Let Service Own its Data: “Singleton” - Part 2
Register()
Registration
Service
(stateless)
Select Count
Add New Row
DatabaseGetCount()
Count Service
(stateful)
State Persisted
and Replicated by
Service Fabric
GetCount()Increment()

17. 17
Let Service Own its Data: Actors
IIndexer
ISearch
Batch of points
Next point
Interface Stateless Service Stateful Actor
Pre-processing &
Normalization
Clusterization &
Storage
Search via
Map & Reduce
Prediction

18. 18
Aggregate, Pre-compute and Delegate
API
(stateless reliable
service)
CRUDCRUD
Azure Search
HTTPS
Publish
Remoting v2HTTPS
Search Adapter
(stateless reliable
service)HTTPS
Index(es) Update
Publish
Analytics
Database(s)
Reporting API
(stateless reliable
service)HTTPS
Queries
TDS/HTTPS/
etc
Analytics Adapter
(stateless reliable
service)
Updates
TDS/HTTPS/
etc
Entity
#xxyyzz
(actor)

19. 19
Where is My State?
• Manage failure domains
• Follow replica recommendations
• Remember that there is no
backup by default!
• Externalize state
• Consider approach when the state
is rebuildable
• Consider cluster periodic backup
(Preview)
• Incorporate backuprestore into
the service (Advanced)

20. 2020
Versioning

21. 21
Versioning Model
MyAppType v 1.0.0
MyServiceType v 1.0.0 MyServiceConfig v 1.0.0

22. 22
A1: 1.0.0
Versioning in Action
S1: 1.0.0
C1: 1.0.0
S2: 1.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
• 3 services in the application
• Single application instance
• Initial version deployed
• Services handle requests

23. 23
A1: 1.0.0
Versioning in Action
S1: 1.0.0
C1: 1.0.0
S2: 1.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
A1: 2.0.0
S1: 1.0.0
C1: 1.0.0
S2: 2.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
• Service S2 is now version 2.0.0
• Application is now version 2.0.0
• Upgrade executed
• S1 and S3 are still running
• S2 started from the new package

24. 24
A1: 1.0.0
Versioning in Action
S1: 1.0.0
C1: 1.0.0
S2: 1.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
A1: 2.0.0
S1: 1.0.0
C1: 1.0.0
S2: 2.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
• S3 config C3 is now version 2.0.0
• Application is now version 3.0.0
• Upgrade executed
• S1 and S2 are still running
• S3 restarted with configuration
from the new package
A1: 3.0.0
S1: 1.0.0
C1: 1.0.0
S2: 2.0.0
C2: 1.0.0
S3: 1.0.0
C3: 2.0.0

25. 25
A1: 1.0.0
Running Versions Side-by-Side
S1: 1.0.0
C1: 1.0.0
S2: 1.0.0
C2: 1.0.0
S3: 1.0.0
C3: 1.0.0
• SF can run multiple app instances
• Same or different version
• Custom instance parameters
• Testing side-by-side
• Advanced upgrade type
• Consider Reverse Proxy
A1: 1.5.0
S1: 1.2.0
C1: 1.2.0
S2: 1.5.0
C2: 1.2.0
S3: 1.5.0
C3: 1.5.1
Instance 1
Instance 2

26. 26
Safe Upgrades
• Proper discovery & retries
• Back/forward state compatibility
• Interface versioning
• Test!
Service Fabric is smart, but it is better to remember the following:

27. 2727
Continuous deployment

28. 28
Simple CICD Pipeline for Service Fabric
Image Store
API
Cluster Manager
Health Manager
Hosting Subsystem

29. 29
Service Fabric Upgrade Flexibility
Upgrade Aspect Default Behavior Other Opportunities
Mode Monitored Unmonitored Manual, Unmonitored Auto
Flow Rolling Upgrade at once with single UD
Health Checks Yes Custom policy, Unmonitored mode
Compatibility Backward and Forward Upgrade in stages to introduce breaking
changes
Rollback Automatic Switch to Unmonitored Manual

30. 30
Keep Your Service Configuration Secure
+
+

31. 31
Thank you