The document discusses using Elastic Load Balancing (ELB) to build a multi-node socket.io architecture. It describes implementing socket.io on a single node initially for an MVP, then adding additional socket.io nodes behind an ELB load balancer for scaling. Key challenges discussed include ensuring sticky sessions work across nodes and enabling messaging between nodes, which is solved using Redis. The architecture is deployed using CodeDeploy and auto-scaling is suggested for future growth.

1. ELB를 활용한 socket.io 멀티노드
구축사례
2017.12.27
박상원 (DeepNatural, Inc.)
anson@deepnatural.io
www.linkedin.com/in/ansonswpark

2. Zamir

3. WebRTC Signaling
Live Match

4. Text Chat

5. 실시간 통신 필요

6. Socket.IO
구현이 간편하고
성능 좋은 비동기 서버
클라이언트 라이브러리도 훌륭함
+
익숙함

7. Minimum
Viable
Product
3달만에 MVP 출시

8. Socket.IO
RESTful API
Django
DRF
uWSGI
Nginx
…
EC2 Single Node
iOS
Client
iOS
Client
ELB
TCP/SSL Mode
HTTP/HTTPS Mode

9. 정식버전 개발시작
Premium Features
In app purchase
..
Multi Node Socket.IO

10. ELB 뒤에 Node 추가

11. Socket.IO
EC2
Socket.IO
EC2
Socket.IO
EC2
iOS
Client
iOS
Client
ELB
TCP/SSL Mode
HTTP/HTTPS Mode

12. Socket.IO
EC2
Socket.IO
EC2
Socket.IO
EC2
iOS
Client
iOS
Client
ELB
TCP/SSL Mode
HTTP/HTTPS Mode
Sticky Session X
Handshake
Multiple Requests
Mixed HTTP & TCP
Socket.IO != WebSocket

15. Application Load Balancer
Launched on August 11, 2016

19. Socket.IO
EC2
Socket.IO
EC2
Socket.IO
EC2
iOS
Client
iOS
Client
ALB Cookie-based Stickiness

20. Socket.IO
EC2
Socket.IO
EC2
Socket.IO
EC2
iOS
Client
iOS
Client
ALB Cookie-based Stickiness
Handshake fails
Cookie handling issue on Socket.IO
client Swift Implementation?
Certificate issue?

21. Working on
Socket.IO Swift Client
Working on
Proxy for Sticky Session
vs
• 클라이언트 개발을 99.9% 마친 상태.
• 클라이언트 수정이 부담됨
• 추후 안드로이드 클라이언트에서 같은 이
슈가 발생한다면?
• 작업 시간 예측이 어려움
• Sticky Connection만 보장되면 문제 해
결됨이 명확
• 서비스 로직 코드 수정 불필요
• 프록시 설정되면, 추후 노드 내에 멀티
프로세스 운영 가능

22. Googling
Best Practice

23. Load-balancing Websockets on EC2
https://medium.com/@Philmod/load-balancing-websockets-on-ec2-1da94584a5e9

24. aws elb create-load-balancer-policy —load-balancer-name elb-storifyeditor
—policy-name EnableProxyProtocol —policy-type-name ProxyProtocolPolicyType
—policy-attributes AttributeName=ProxyProtocol,AttributeValue=True
aws elb set-load-balancer-policies-for-backend-server —load-balancer-name
elb-storifyeditor —instance-port 3030 —policy-names EnableProxyProtocol
HAProxy가 클라이언트 IP Address 기반 Sticky Connection 제공할 수 있도록 ELB
에 Proxy Protocol 활성화
Load-balancing Websockets on EC2
https://medium.com/@Philmod/load-balancing-websockets-on-ec2-1da94584a5e9

25. Socket.IO Socket.IO Socket.IO
iOS
Client
iOS
Client
ELB
TCP Mode
Proxy Protocol Enabled
HAProxy HAProxy HAProxy

26. Messaging
between Nodes

27. Socket.IO Socket.IO Socket.IO
BA
ELB
HAProxy HAProxy HAProxy
다른 노드에 붙은 두 클라이언트 A, B.
A에서 B로 메시지 보내기 불가능

28. Socket.IO Socket.IO Socket.IO
BA
ELB
HAProxy HAProxy HAProxy
ElastiCache
Redis Cluster
ElastiCache
+
Socket.IO Redis Adapter

29. https://github.com/socketio/socket.io-redis

30. Deployment

31. Socket.IO Socket.IO Socket.IO
iOS
Client
iOS
Client
ELB
TCP Mode
Proxy Protocol Enabled
HAProxy HAProxy HAProxy Fabric Script
Code deploy
ElastiCache
Redis Cluster
Launch new instance
Socket.IO setup
HAProxy setup & update

32. Socket.IO Socket.IO Socket.IO
iOS
Client
iOS
Client
ELB
TCP Mode
Proxy Protocol Enabled
HAProxy HAProxy HAProxy Fabric Script
Code deploy
ElastiCache
Redis Cluster
Launch new instance
Socket.IO setup
HAProxy setup & update

33. 서비스가 다음 단계로
성장한다면

34. https://medium.com/@eyalronel1984/auto-scaling-real-
time-nodejs-applications-on-aws-the-last-tutorial-youll-
need-eba1d2c88a4c
Auto Scaling Real-Time NodeJS Applications on
AWS — The last tutorial you’ll need!

35. 자미르 메이저 업데이트 커밍순
https://zamir.io/

36. talk
anson@deepnatural.io
www.linkedin.com/in/ansonswpark