你好！我叫Kirill，我是Adapty的CTO。我们的大多数架构都在AWS上，今天我将讨论如何通过在生产环境中使用Spot实例将服务器成本降低3倍，以及如何将它们设置为自动伸缩。首先将概述其工作原理，然后是详细的启动说明。
什么是竞价型实例？
竞价型实例是当前处于闲置状态的其他AWS用户服务器，并且它们以很高的折扣出售（亚马逊的写入量高达90％，根据我们的经验，约为三倍，具体取决于区域，可用区和实例类型）。它们与传统产品的主要区别在于它们可以随时关闭。因此，长期以来，我们认为将它们用于原始环境或进行计算任务是正常的，并且将中间结果保存在S3或基础上，而不是用于销售。有第三方解决方案可以让您使用特价商品，但是由于我们的案例很多，因此我们没有实施。本文中描述的方法完全在标准AWS功能内运行，而无需其他脚本，王冠等。
以下是一些屏幕快照，显示了竞价型实例价格的历史记录。
位于eu-west-1地区（爱尔兰）的m5.large。价格大多稳定3个月，目前可节省2.9倍。
在us-east-1地区（弗吉尼亚北部）的m5.large。价格已经连续3个月变化，根据不同的可用区域，目前节省的费用是2.3倍至2.8倍。
t3.small在美国东1区（N.弗吉尼亚州）。价格稳定3个月，目前可节省3.4倍。
服务架构
下图显示了我们将在本文中讨论的服务的基本体系结构。
Application Load Balancer → EC2 Target Group → Elastic Container Service
Application Load Balancer (ALB), EC2 Target Group (TG). TG , ALB Elastic Container Service (ECS). ECS — Kubernetes AWS, Docker .
, . ECS TG, ( Kubernetes ), . TG , health check, - , .
EC2 Auto Scaling Groups + ECS Capacity Providers
EC2 Auto Scaling Groups (ASG). , . AWS ECS. ECS , , CPU, RAM . , .
ECS Capacity Providers (ECS CP). ECS ASG, , ( ASG). , ECS CP , ASG, . ECS CP , , , .
EC2 Launch Templates
, , , — EC2 Launch Templates. , , . , , . , . , , ECS .
— ECS_ENABLE_SPOT_INSTANCE_DRAINING=true. , ECS , , , Draining. , , , . . 2 . 2 , .
— AWS Elastic File System (EFS) ECS, , , . SIGINT ( Draining) 30 , , ECS_CONTAINER_STOP_TIMEOUT. 2 .
. , . , - . AWS, CloudFormation Terraform. Adapty Terraform.
EC2 Launch Template
, . EC2 -> Instances -> Launch templates.
Amazon machine image (AMI) — , . ECS Amazon. ECS. ID , Amazon ECS-optimized AMIs, AMI ID . , us-east-1 ID — ami-00c7c1cf5bdc913ed. ID Specify a custom value.
Instance type — . , .
Key pair (login) — , SSH, .
Network settings — . Networking platform Virtual Private Cloud (VPC). Security groups — . , , . 2 , , (inbound) 80 (http) 443 (https), , . (outbound) TCP . , , - .
Storage (volumes) — . , AMI, ECS Optimized — 30 GiB.
Advanced details — .
Purchasing option — . , , Auto Scaling Group, .
IAM instance profile — , . , ECS, , ecsInstanceRole. , , , . .
, , . EBS-optimized instance T2/T3 Unlimited, burstable .
User data — . /etc/ecs/ecs.config, ECS.
, user data:
#!/bin/bash
echo ECS_CLUSTER=DemoApiClusterProd >> /etc/ecs/ecs.config
echo ECS_ENABLE_SPOT_INSTANCE_DRAINING=true >> /etc/ecs/ecs.config
echo ECS_CONTAINER_STOP_TIMEOUT=1m >> /etc/ecs/ecs.config
echo ECS_ENGINE_AUTH_TYPE=docker >> /etc/ecs/ecs.config
echo "ECS_ENGINE_AUTH_DATA={\"registry.gitlab.com\":{\"username\":\"username\",\"password\":\"password\"}}" >> /etc/ecs/ecs.configECS_CLUSTER=DemoApiClusterProd — , , . , .
ECS_ENABLE_SPOT_INSTANCE_DRAINING=true — , , Draining.
ECS_CONTAINER_STOP_TIMEOUT=1m — , SIGINT, 1 , .
ECS_ENGINE_AUTH_TYPE=docker — , docker-
ECS_ENGINE_AUTH_DATA=... — container registry, Docker . , .
Docker Hub, ECS_ENGINE_AUTH_TYPE ECS_ENGINE_AUTH_DATA .
: AMI, Docker, Linux, ECS . , . email , Lambda-, Launch Template AMI.
EC2 Auto Scaling Group
Auto Scaling Group . EC2 -> Auto Scaling -> Auto Scaling Groups.
Launch template — . .
Purchase options and instance types — . Adhere to launch template Launch Template. Combine purchase options and instance types . .
Optional On-Demand base — , , .
On-Demand percentage above base — , 50-50 , 20-80 4 . 50-50, 20-80, 0-100.
Instance types — , . , . , . , )
Network — , VPC , .
Load balancing — , , . Health checks .
Group size — . , .
Scaling policies — , , ECS , .
Instance scale-in protection — . , ASG , . , , ECS Capacity Provider.
Add tags — ( Tag new instances). Name, , , , .
Advanced configurations, .
Termination policies — , . . , . Launch Template (, AMI, , ). , . .
: , Instance Refresh. Lambda- , . instance scale-in protection . , , Instance management.
Application Load Balancer EC2 Target Group
EC2 → Load Balancing → Load Balancers. Application Load Balancer, .
Listeners — 80 443 80 443 .
Availability Zones — .
Configure Security Settings — SSL- , — ACM. Security Policy , ELBSecurityPolicy-2016-08. , DNS name, CNAME . , Cloudflare.
Security Group — , EC2 Launch Template → Network settings.
Target group — , , . Target type Instance, Protocol Port , HTTPS , . , 80 .
Health checks — . , -, -. , , . Success codes 200-399, Docker , , 304 .
Register Targets — , ECS, .
: , S3 . , SQL- S3 Athena. - . S3 .
ECS Task Definition
, , , . ECS → Task Definitions.
Launch type compatibility — EC2.
Task execution IAM role — ecsTaskExecutionRole. , .
Container Definitions Add Container.
Image — , Docker Hub bitnami/node-example:0.0.1.
Memory Limits — . Hard Limit — , , docker kill, . Soft Limit — , , . , 4 GiB , soft limit — 2048 MiB, 2 . 4 GiB — , 4096 MiB, ECS Instances . Soft limit hard limit. , , .
Port mappings — Host port 0, , , Target Group. Container Port — , , , , Dockerfile . 3000, Dockerfile .
Health check — , , Target Group.
Environment — . CPU units — Memory limits, . — 1024 , , 512, 4 . CPU units , .
Command — , . gunicorn, npm . , CMD Dockerfile. npm,start.
Environment variables — . , Secrets Manager Parameter Store.
Storage and Logging — CloudWatch Logs ( AWS). Auto-configure CloudWatch Logs. Task Definition CloudWatch. , Retention period Never Expire . CloudWatch Log groups, .
ECS Cluster ECS Capacity Provider
ECS → Clusters, . EC2 Linux + Networking.
Cluster name — , , Launch Template ECS_CLUSTER, — DemoApiClusterProd. Create an empty cluster. Container Insights, CloudWatch. , ECS Instances , Auto Scaling group.
Capacity Providers . , , ECS . , .
Auto Scaling group — .
Managed scaling — , .
Target capacity % — . 100%, . 50%, . , , , .
Managed termination protection — , . , Target capacity %.
ECS Service
:) , Services.
Launch type — Switch to capacity provider strategy .
Task Definition — Task Definition .
Service name — , , Task Definition.
Service type — Replica.
Number of tasks — . , .
Minimum healthy percent Maximum percent — . 100 200, , 2 , . 1 , min=0, max=100, , , . 1 , min=50, max=150, , 1 .
Deployment type — Rolling update.
Placement Templates — . AZ Balanced Spread — , , . BinPack — CPU Spread — AZ, CPU. , .
Load balancer type — Application Load Balancer.
Service IAM role — ecsServiceRole.
Load balancer name — .
Health check grace period — , 60 .
Container to load balance — Target group name , .
Service Auto Scaling — . Configure Service Auto Scaling to adjust your service’s desired count. .
IAM role for Service Auto Scaling — AWSServiceRoleForApplicationAutoScaling_ECSService.
Automatic task scaling policies — . 2 :
- Target tracking — ( CPU/RAM ). , 85%, , , . , , (Disable scale-in).
- Step scaling — . (CloudWatch Alarm), , , .
, , , .
Docker , .
- , . .
- , , .
- , .
- , , 3 .
- , , .
- Capacity Provider, (), .
- .
. , - . 1+ . API, . , - , , .
, ECS - .
, serverless ( ) GitLab CI Terraform Cloud.
, !