233 lines
5.4 KiB
Markdown
233 lines
5.4 KiB
Markdown
---
|
|
id: devops-finops-cost
|
|
title: FinOps — Cloud cost / Tagging / 최적화
|
|
category: Coding
|
|
status: draft
|
|
source_trust_level: B
|
|
verification_status: conceptual
|
|
created_at: 2026-05-09
|
|
updated_at: 2026-05-09
|
|
tags: [devops, finops, cost, vibe-coding]
|
|
tech_stack: { language: "Terraform / AWS", applicable_to: ["DevOps"] }
|
|
applied_in: []
|
|
aliases: [FinOps, cloud cost, tagging, RI, savings plan, spot, rightsizing]
|
|
---
|
|
|
|
# FinOps
|
|
|
|
> Cloud bill 가 OOC (out of control). **Tag → cost allocation, RI / Savings Plan, spot, rightsizing, idle 제거** 5종. 보통 30-50% 절감 가능.
|
|
|
|
## 📖 핵심 개념
|
|
- Tag: 자원에 메타 (env, team, project).
|
|
- Cost allocation: tag 기반 청구.
|
|
- Reserved / Savings: 1년+ 약정 = 30-70% 할인.
|
|
- Spot: 대기 가능한 작업 = 70-90% 할인.
|
|
|
|
## 💻 코드 패턴
|
|
|
|
### Tagging strategy
|
|
```hcl
|
|
# Terraform — default tags
|
|
provider "aws" {
|
|
default_tags {
|
|
tags = {
|
|
Environment = var.env
|
|
Team = var.team
|
|
Project = var.project
|
|
CostCenter = var.cost_center
|
|
ManagedBy = "terraform"
|
|
}
|
|
}
|
|
}
|
|
```
|
|
|
|
→ AWS Cost Explorer 가 tag 별 청구 분석.
|
|
|
|
### IAM 강제 — 미태그 금지
|
|
```json
|
|
{
|
|
"Effect": "Deny",
|
|
"Action": ["ec2:RunInstances", "rds:CreateDBInstance"],
|
|
"Resource": "*",
|
|
"Condition": {
|
|
"Null": { "aws:RequestTag/Team": "true" }
|
|
}
|
|
}
|
|
```
|
|
|
|
### 비용 모니터링
|
|
```ts
|
|
// AWS Cost Explorer API
|
|
const ce = new AWS.CostExplorer({ region: 'us-east-1' });
|
|
const r = await ce.getCostAndUsage({
|
|
TimePeriod: { Start: '2026-05-01', End: '2026-05-09' },
|
|
Granularity: 'DAILY',
|
|
Metrics: ['UnblendedCost'],
|
|
GroupBy: [{ Type: 'TAG', Key: 'Team' }],
|
|
}).promise();
|
|
```
|
|
|
|
```yaml
|
|
# Slack alert if cost spike
|
|
- alert: DailyCostSpike
|
|
expr: aws_cost_today > 2 * aws_cost_avg_7d
|
|
```
|
|
|
|
### Reserved Instances / Savings Plans
|
|
```
|
|
On-demand: $100/month
|
|
Reserved 1y: $60 (40% off)
|
|
Reserved 3y: $40 (60% off)
|
|
Savings Plan: $50 (50% off, 더 유연)
|
|
```
|
|
|
|
→ 안정적 baseline = RI / SP. spike = on-demand.
|
|
|
|
### Spot instances
|
|
```hcl
|
|
resource "aws_instance" "worker" {
|
|
instance_market_options {
|
|
market_type = "spot"
|
|
spot_options { max_price = "0.05" }
|
|
}
|
|
}
|
|
```
|
|
|
|
→ 1-2분 알림 후 종료. Stateless / batch / autoscaling group.
|
|
|
|
```hcl
|
|
# K8s — Karpenter
|
|
provisioner:
|
|
spec:
|
|
requirements:
|
|
- { key: karpenter.sh/capacity-type, operator: In, values: [spot, on-demand] }
|
|
```
|
|
|
|
### Rightsizing
|
|
```bash
|
|
# CloudWatch + Compute Optimizer
|
|
aws compute-optimizer get-ec2-instance-recommendations
|
|
# → "이 t3.large 는 t3.small 로 충분"
|
|
```
|
|
|
|
→ CPU / memory < 20% 사용 = 작게.
|
|
|
|
### Idle 자원 (가장 흔한 낭비)
|
|
```bash
|
|
# 미사용 EBS volumes
|
|
aws ec2 describe-volumes --filters Name=status,Values=available
|
|
|
|
# Idle ELB (no traffic)
|
|
# Stopped EC2 (EBS 비용 그대로)
|
|
# Old snapshots
|
|
aws ec2 describe-snapshots --owner-ids self --query 'Snapshots[?StartTime<`2025-01-01`]'
|
|
|
|
# Unused EIP
|
|
aws ec2 describe-addresses --filters Name=association-id,Values=
|
|
```
|
|
|
|
```bash
|
|
# 매일 정리
|
|
aws ec2 delete-volume --volume-id $UNATTACHED
|
|
```
|
|
|
|
### Scheduled scaling (dev)
|
|
```hcl
|
|
# Dev 환경 = 9-18 만 켜기 (50% 절감)
|
|
resource "aws_autoscaling_schedule" "off" {
|
|
scheduled_action_name = "off-evening"
|
|
recurrence = "0 18 * * 1-5"
|
|
desired_capacity = 0
|
|
...
|
|
}
|
|
|
|
resource "aws_autoscaling_schedule" "on" {
|
|
scheduled_action_name = "on-morning"
|
|
recurrence = "0 9 * * 1-5"
|
|
desired_capacity = 2
|
|
}
|
|
```
|
|
|
|
### Data transfer (숨은 비용)
|
|
```
|
|
Same-AZ: free
|
|
Cross-AZ: $0.01/GB
|
|
Cross-region: $0.02-0.09/GB
|
|
Internet egress: $0.05-0.09/GB
|
|
|
|
NAT gateway: $0.045/GB + $0.045/hour
|
|
→ VPC endpoint 로 S3 / DynamoDB 직접 (free)
|
|
```
|
|
|
|
### S3 storage class
|
|
```
|
|
Standard: $23/TB/mo
|
|
Intelligent-Tier: 자동 전환
|
|
Standard-IA: $12.5/TB/mo (가끔 access)
|
|
Glacier: $4/TB/mo (long backup)
|
|
Glacier Deep: $1/TB/mo (rare)
|
|
```
|
|
|
|
```hcl
|
|
resource "aws_s3_bucket_lifecycle_configuration" "main" {
|
|
rule {
|
|
status = "Enabled"
|
|
transition { days = 30; storage_class = "STANDARD_IA" }
|
|
transition { days = 90; storage_class = "GLACIER" }
|
|
}
|
|
}
|
|
```
|
|
|
|
### Budget alarm
|
|
```hcl
|
|
resource "aws_budgets_budget" "monthly" {
|
|
name = "monthly"
|
|
budget_type = "COST"
|
|
limit_amount = "10000"
|
|
limit_unit = "USD"
|
|
time_unit = "MONTHLY"
|
|
|
|
notification {
|
|
threshold = 80
|
|
threshold_type = "PERCENTAGE"
|
|
notification_type = "ACTUAL"
|
|
subscriber_email_addresses = ["finance@acme.com"]
|
|
}
|
|
}
|
|
```
|
|
|
|
### LLM cost (위 AI_LLM_Cost_Optimization)
|
|
```
|
|
LLM = 새로운 cloud bill. 별도 추적.
|
|
```
|
|
|
|
## 🤔 의사결정 기준
|
|
| 절감 영역 | 우선순위 |
|
|
|---|---|
|
|
| Idle 자원 | 즉시 (매주 cleanup) |
|
|
| Rightsizing | 월별 |
|
|
| Tag + visibility | 즉시 |
|
|
| RI / Savings | 6개월 안정 후 |
|
|
| Spot | Stateless 작업 |
|
|
| Data transfer | VPC endpoint |
|
|
| S3 lifecycle | 항상 |
|
|
|
|
## ❌ 안티패턴
|
|
- **Tag 없음**: cost 누구 책임 모름.
|
|
- **모든 자원 on-demand**: RI / SP 없으면 30-70% 더.
|
|
- **Dev 24h 켜둠**: 70% 낭비.
|
|
- **Spot prod stateful**: 강제 종료 시 데이터 잃음.
|
|
- **Snapshot / EBS / EIP 청소 X**: 매월 누적.
|
|
- **Cross-AZ 무절제**: $$$/GB.
|
|
- **Cost monitoring 없음**: 청구서 보고 놀람.
|
|
|
|
## 🤖 LLM 활용 힌트
|
|
- Tag → visibility → 액션.
|
|
- Idle 청소가 가장 ROI.
|
|
- Spot + Karpenter 자동.
|
|
|
|
## 🔗 관련 문서
|
|
- [[DevOps_Terraform_Patterns]]
|
|
- [[DevOps_Kubernetes_Basics]]
|
|
- [[AI_LLM_Cost_Optimization]]
|