Serverless Architecture म्हणजे काय? कधी वापरायचं आणि कधी नाही

By Ravindra Bagale, trainer · LinkedIn · Last updated: 2 November 2026

1. रोजचे उदाहरण: मागणीवरचा चहा स्टॉल

Ravi ऑर्डर आल्यावरच पाणी उकळवतो. Priya (Bengaluru) PDF invoice API तशीच. Always-on EC2 रात्री वाया. API Gateway+Lambda per invoice उठते. हेच serverless architecture.

Serverless = servers नाहीत नव्हे. Servers AWS मध्ये. SSH/patch/fleet तुमचे काम नाही.

पूर्ण system आधी What Is AWS Lambda? refresh करा. हा chapter architecture.

2. Architecture view का?

हे का लागतं?

पाच tutorials = architecture नव्हे. Recursive S3, DLQ नाही, surprise bills. Architecture आधी fit/limits/failure/cost.

हे काय आहे?

Serverless architecture = managed event-driven services + patterns.

3. Vertical diagram

4. तुम्ही शिकलेले blocks

हे काय आहे?

• Compute: What Is AWS Lambda?.
• HTTP: API Gateway.
• Data: DynamoDB.
• Messaging: SQS and SNS.
• Events: EventBridge.
• Orchestration: Step Functions.
• Identity: Cognito.

Live projects: notes app project, URL shortener. Patterns link — source paste नाही.

5. कधी चमकतं

• Spiky traffic.
• Glue work.
• Small APIs.
• Cron.
• Prototypes.

6. कधी नको

7. Decision table

8. Sketch कसा

कसं करायचं (step by step)

1. 5 bullets, no AWS names.
2. Sync vs async.
3. Map sync/async.
4. Data from access patterns.
5. Auth+observe+failure.
6. 10x cost.
7. मग console/IaC.

Functions list

aws lambda list-functions --region ap-south-1 --query 'Functions[].FunctionName' --output table

अर्थ: नवीन hello आधी existing बघा.

Concurrency ceiling

aws lambda get-account-settings --region ap-south-1 --query 'AccountLimit.[ConcurrentExecutions,UnreservedConcurrentExecutions]'

अर्थ: Load test आधी ceiling.

9. Lab: कागद + console

Org block नसेल तर ap-south-1 (Mumbai). आधी budget alert.

कसं करायचं (step by step)

1. create-order diagram.
2. Sync/async + idempotency.
3. Dashboard read-only.
4. p99 vs timeout.
5. एक वाक्य.

Cleanup (billing थांबवा)

1. Test function delete.
2. आजचे log groups.

10. Mini-examples

Python: async?

def prefer_async(user_waits, work_ms):
    if not user_waits: return True
    return work_ms > 2500
print(prefer_async(True, 800))
print(prefer_async(True, 8000))
print(prefer_async(False, 100))

Output: False/True/True. अर्थ: लांब wait = queue.

Node: GB-seconds

const gbSec=(mb,ms,n)=>(mb/1024)*(ms/1000)*n;
console.log(gbSec(512,200,1_000_000)); // 100000

अर्थ: ≈100k GB-s. Pricing page बघा.

11. Stack stories

1. FastAPI peel /invoices.
2. Node bounded context.
3. Java -> ECS via Lambda.
4. .NET on Lambda.
5. Go ESM.
6. PHP hybrid.

12. Commands + meaning

Function timeout

aws lambda get-function-configuration --function-name hello-lambda-lab --region ap-south-1 --query '[Timeout,MemorySize]'

अर्थ: Timeout vs p99.

Log groups

aws logs describe-log-groups --log-group-name-prefix /aws/lambda/ --region ap-south-1 --max-items 5

अर्थ: Logs कुठे पडतात ते बघा.

13. एकाच pattern — वेगवेगळ्या industries

• Fintech (Aisha, Lagos): payment webhooks → SQS → Lambda.
• Ecommerce (Rohan, Pune): checkout API; inventory SNS fan-out.
• Healthcare (Mei, Singapore): SNS SMS; PHI + fine-grained IAM.
• EdTech (Diego, São Paulo): EventBridge nightly cleanup.
• Logistics (Fatima, Casablanca): EventBridge + saga.
• Media (Kenji, Osaka): S3 → Lambda thumbs + fan-out.
• SaaS (Priya, Bengaluru): Cognito + per-tenant partition.
• Gov (Omar, Amman): strangler fig per form route.

14. Troubleshooting checklist

1. Region confirm करा.
2. CloudWatch Logs + request id.
3. Execution role permissions.
4. DLQ + oldest message age.
5. curl -v + CORS.
6. SFN event history.
7. Linked chapter पुन्हा वाचा.
8. Cost: concurrency/retries.

15. सामान्य errors आणि fixes

प्रत्येक row = खरी चूक. Panic करण्याआधी fix वाचा.

16. FAQ

17. Interview Q&A (Beginner / Mid / Senior + MNC)

18. Tips — English, मराठी आणि हिंदी

19. Code आधी cost gut-check

Priya receipt API: 2M invokes, 256MB, 150ms. GB-s ≈ 75k. Free tier शक्य; APIGW+DDB वेगळे. ap-south-1 pricing page बघा.

Python: rough compute

def gb_seconds(mb, ms, invokes):
    return (mb/1024.0) * (ms/1000.0) * invokes
print(round(gb_seconds(256, 150, 2_000_000)))
print(round(gb_seconds(1024, 3000, 100_000)))

Output: 75000 / 300000. अर्थ: memory+duration > फक्त invoke count.

20. Failure paths

हे काय आहे?

1. Sync: stable JSON errors.
2. Async: DLQ + alarm.
3. Fan-out partial fail.
4. SFN retries + compensate.
5. Auth at edge.

21. Observability starter

• JSON logs + requestId.
• Business metric.
• Alarms.
• X-Ray/Powertools later.

Log streams

aws logs describe-log-streams --log-group-name /aws/lambda/hello-lambda-lab \
  --order-by LastEventTime --descending --max-items 3 --region ap-south-1

अर्थ: Insights आधी logs येतात का ते बघा.

22. Anti-pattern deep dive

23. Migration sketch

Weekend rewrite नको. Strangler chapter: APIGW front, एक route peel. आज: पहिला peel candidate लिहा.

1. Top 10 routes.
2. Low shared state.
3. Read-heavy peel #1.
4. Metrics आधी.

24. पहिल्या production cut साठी checklist

1. Budget + anomaly.
2. IAM second review.
3. DLQ + alarm.
4. Runbook in alarm.
5. Load test 2x.
6. Rollback alias.
7. PITR if money/PII.
8. when-NOT documented.

दोन missing असतील तर अजून lab — production म्हणू नका.

25. Architecture decision checklist

1. User journey 5 bullets, no AWS names.
2. Sync vs async mark.
3. Failure mode.
4. Idempotency key.
5. Data from access patterns.
6. Cost 1x and 10x.
7. Quotas ap-south-1.
8. Auth decision.
9. On-call + alarm.
10. Deep chapter link.
11. मग console/IaC.

26. Copy-paste quick commands

# Region and identity
aws configure get region
aws sts get-caller-identity

# Lambda landscape
aws lambda list-functions --region ap-south-1 --max-items 20 \
  --query 'Functions[].{N:FunctionName,R:Runtime,T:Timeout,M:MemorySize}' --output table
aws lambda get-account-settings --region ap-south-1

# API Gateway (HTTP APIs)
aws apigatewayv2 get-apis --region ap-south-1 --query 'Items[].{N:Name,Id:ApiId,Ep:ProtocolType}' --output table

# Queues and topics
aws sqs list-queues --region ap-south-1
aws sns list-topics --region ap-south-1 --query 'Topics[].TopicArn'

# Event buses and state machines
aws events list-event-buses --region ap-south-1
aws stepfunctions list-state-machines --region ap-south-1 --query 'stateMachines[].name'

# DynamoDB tables (names only)
aws dynamodb list-tables --region ap-south-1

Sandbox + read-only IAM.

27. अजून industry आणि stack stories

• Fintech Lagos: webhook → SQS → idempotent ledger.
• Ecommerce Pune: throttle + fan-out.
• Healthcare SG: SNS + PHI IAM.
• EdTech: EventBridge cleanup.
• Logistics: bus + saga.
• Media: avoid recursive S3.
• SaaS: tenant partition.
• Gov: strangler peel.
• Startup: Function URL → HTTP API.
• Retail: FIFO vs Standard.

• Python: thin handlers.
• Node: async/await.
• Java: SnapStart.
• .NET: package size.
• Go: static binary.
• PHP: hybrid.

28. Glossary

29. Practice: मोठ्याने explain

1. 60s: serverless architecture गोष्ट.
2. 60s: sync vs async checkout.
3. 60s: Lambda नको कधी.
4. 60s: DLQ + idempotency.
5. Record ×2.

30. Safe lab hygiene

• Tag owner+expiry.
• Budget alarm आधी.
• Read-only first.
• Cleanup.
• No secrets in env/screenshots.
• No provisioned on hello.

31. या chapter च्या links

• Compute: Lambda.
• HTTP: API Gateway.
• Data: DynamoDB.
• Messaging: SQS/SNS.
• Events: EventBridge.
• Workflows: Step Functions.
• build-* projects link.

32. Myths

33. Serverless error budget

Checkout error budget 0.1% असेल तर aggressive retries email duplicates देऊन budget जाळू शकतात. Money SLO ≠ notify SLO.

1. दोन SLOs.
2. Money retries bounded.
3. Notify best-effort.
4. Money page; notify ticket.

34. Regional notes (ap-south-1)

• Labs Mumbai.
• Feature availability.
• Data residency.
• Latency India.

35. Naming conventions

# Suggested prefixes
# Lambda:  pay-intake-prod, pay-worker-prod
# SQS:     pay-orders.fifo / pay-orders-dlq
# SNS:     pay-order-events
# EB bus:  pay.domain
# SFN:     pay-refund-saga
# DDB:     pay-orders-prod

env + domain नावात ठेवा. CloudWatch grep सोपा.

36. Pre-mortems

1. Double charge headline.
2. DLQ drain plan.
3. Cognito outage mode.
4. Runbook.

37. Currency / locale

Currencies आणि names rotate करा — global mental model.

उजळणी, मुलाखत आणि तुलना cards

हा lesson काही मिनिटांत revise करा. Cards phone वर save करा किंवा PNG download करा. प्रत्येक card वरचा QR हा lesson उघडतो.

अजून cards: Ravi Sir's Cards.