Ops

 TALKS

Knowledge worth sharing

#03

Florian Dambrine - Principal Engineer - @GumGum

K8s & ECS

Agenda

What DOES it DO

***

Basics

***

DEEP dive

***

CHEATSHEET

What does it do

/ K8s / ECS /

K8s / ECS

K8s

ECS

Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services

ECS is a fully managed container orchestration service

  • Service discovery and load balancing
  • Storage orchestration
  • Automated rollouts and rollbacks 
  • Self-healing
  • Secret and configuration management
  • Integrated with AWS services
  • Easy to pick up

k8s / ecs

  • Entry level to container world
  • Ease of use from GUI
  • ecs-cli and aws-cli as a way to interact with the cluster
  • API Driven - Kubernetes is first and foremost a REST API
  • Restricted access to K8s control plane on AWS
  • kubectl as a way to interact with the cluster

k8s / ecs - why switching over

  • Local environment available in multiple flavors to build complex dev eco-system or just test locally (no local ECS dev)
  • More reactive than ECS
  • Can plug directly into Prometheus for scaling
  • Better deployment orchestration (no downtime)
  • Much more features than ECS
    • Configmaps (Configuration dropped inside a volume to be used by the container)
    • Init containers
    • Ingress containers (Creation of ELBs from K8s)
    • Volumes and EFS (mount per pod, not at the EC2 level)

Basics

MAIN CONCEPTS/ Basic Navigation

- Main concepts -

cluster
service / deployment
pods / tasks
volumes / autoscaling

Main concepts - ECS Vs K8s - Terms

Cluster Cluster
Service & Task definition Deployment
Task Pod
Volume PersistentVolume

Service

Tasks

Task definition

Basic navigation - AuthenticatioN

### Requirements: 
###   * Install aws-cli
aws ecs list-clusters
{
    "clusterArns": [
        "arn:aws:ecs:us-east-1:123456789910:cluster/va-mle--prod",
        "arn:aws:ecs:us-east-1:123456789910:cluster/va-mle-inference--prod",
        ...
    ]
}
### Requirements: 
###   * Install Kubectl EKS Vendored (mac version)
###   * Install aws-cli >= 1.16.156 (replacement of aws-iam-authenticator)

### Update `~/.kube/config` with EKS cluster config and alias it as `k8s-mle`
aws eks update-kubeconfig --name va-verity-prod-eks --alias verity-prod

### Set your client to connect to verity-prod in namespace monitoring
kubectl config set-context verity-prod --namespace=monitoring \
  && kubectl config

### List nodes running in the cluster
kubectl get nodes
NAME                            STATUS   ROLES    AGE   VERSION
ip-10-201-116-76.ec2.internal   Ready    <none>   16h   v1.17.9-eks-4c6976
ip-10-201-24-166.ec2.internal   Ready    <none>   22m   v1.17.9-eks-4c6976
ip-10-201-41-15.ec2.internal    Ready    <none>   13h   v1.17.9-eks-4c6976

BASIC NAVIGATION - Select CLUSTER

### List services running in the cluster va-mle--prod
aws ecs list-clusters
{
    "clusterArns": [
        "arn:aws:ecs:us-east-1:123456789910:cluster/va-mle--prod",
        "arn:aws:ecs:us-east-1:123456789910:cluster/va-mle-inference--prod",
        ...
    ]
}
### Set your client to connect to verity-prod in namespace default
kubectl config set-context verity-prod --namespace=default \
  && kubectl config use-context verity-prod

/// OR ///

## Switch to cluster verity-prod namespace default
kubectx verity-prod
kubens default

### List pods running in the cluster namespace
kubectl get nodes
NAME                            STATUS   ROLES    AGE   VERSION
ip-10-201-116-76.ec2.internal   Ready    <none>   16h   v1.17.9-eks-4c6976
ip-10-201-24-166.ec2.internal   Ready    <none>   22m   v1.17.9-eks-4c6976
ip-10-201-41-15.ec2.internal    Ready    <none>   13h   v1.17.9-eks-4c6976

BASIC NAVIGATION - View services / deployments

### List services running in the cluster va-mle--prod
aws ecs list-services --cluster va-mle--prod
{
    "serviceArns": [
        "arn:aws:ecs:us-east-1:12345678910:service/video-transcribe__prod",
        ...
    ]
}
## List all running deployments in the cluster
kubectl get deployments --all-namespaces
NAME                                               READY   UP-TO-DATE   AVAILABLE   AGE
ai-kafka-lag-reporting--production-burrow          1/1     1            1           23d
ai-kafka-lag-reporting--production-karrot          1/1     1            1           23d
ai-kafka-lag-reporting--staging-burrow             1/1     1            1           16d
ai-kafka-lag-reporting--staging-karrot             1/1     1            1           16d
kafka-manager--production                          1/1     1            1           23d
...

BASIC NAVIGATION - View PODs / tasks

### List services running in the cluster va-mle--prod
aws ecs list-tasks --cluster va-mle--prod
{
    "taskArns": [
        "arn:aws:ecs:us-east-1:12345678910:task/va-mle--prod/08e6004b550c4adc8d760e6ef8618482",
        ...
    ]
}
## List all running pods in the cluster
kubectl get pods --all-namespaces
NAME                                                              READY   STATUS    RESTARTS   AGE
ai-kafka-lag-reporting--production-burrow-695d887765-6g2mz        1/1     Running   0          59m
ai-kafka-lag-reporting--production-karrot-769748dcd9-wl7bc        1/1     Running   0          59m
ai-kafka-lag-reporting--staging-burrow-75f69ff888-k5hcq           1/1     Running   0          59m
ai-kafka-lag-reporting--staging-karrot-6b9d66d985-hhr7w           1/1     Running   0          59m
kafka-manager--production-6dcb578fc-bnfpb                         1/1     Running   0          59m
prometheus-mle--production-alertmanager-6f57c4684b-dw9xs          2/2     Running   0          14h
prometheus-mle--production-kube-state-metrics-6c88687bd8-jkmfc    1/1     Running   0          59m
prometheus-mle--production-pushgateway-5b9dbd7f94-s9rb2           1/1     Running   0          59m
prometheus-mle--production-server-688cb4bf47-bdrw2                2/2     Running   0          59m
prometheus-nlp--production-alertmanager-cb88575cb-58xxf           2/2     Running   0          59m
prometheus-nlp--production-kube-state-metrics-5fb889bbc8-qnkzp    1/1     Running   0          59m
prometheus-nlp--production-pushgateway-64f76bfc48-rv2qb           1/1     Running   0          59m
prometheus-nlp--production-server-7565ffb9b9-rk6bn                2/2     Running   0          16h
prometheus-verity--production-alertmanager-6794ddd944-8chvf       2/2     Running   0          59m

BASIC NAVIGATION - INSPECT SERVICE SPECS

### Inspect task specs from cluster va-mle--prod
aws ecs describe-tasks --cluster va-mle--prod --task-arn arn:aws:ecs:us-east-1:12345678910:task/va-mle--prod/08e6004b550c4adc8d760e6ef8618482
{

    "tasks": [
        {
            "attachments": [],
            "availabilityZone": "us-east-1e",
            "clusterArn": "arn:aws:ecs:us-east-1:12345678910:cluster/va-mle--prod",
            "connectivity": "CONNECTED",
            "connectivityAt": 1603390576.188,
            "containerInstanceArn": "arn:aws:ecs:us-east-1:12345678910:container-instance/va-mle--prod/8e5d58e75ce5423a91550ff7731ad373",
            "containers": [
                {
                    "containerArn": "arn:aws:ecs:us-east-1:12345678910:container/d72d8b0d-fd0f-43ab-8cbb-394a092f9cc1",
                    "taskArn": "arn:aws:ecs:us-east-1:12345678910:task/va-mle--prod/08e6004b550c4adc8d760e6ef8618482",
                    "name": "prism-api",
                    "image": "12345678910.dkr.ecr.us-east-1.amazonaws.com/gumgum/machine-learning-engineering/prism-api:0.9.3",
                    "imageDigest": "sha256:ad8d6a83347f83c862cfcae638bafa4cf0cd6fd53ae646b5a6c0be875ec2b3dd",
                    "runtimeId": "88ba0668d15aac5186f3a88ba68f802f952aa4641192661589fdba8b5e972a0b",
                    "lastStatus": "RUNNING",
                    "networkBindings": [
                        {
                            "bindIP": "0.0.0.0",
                            "containerPort": 8080,
                            "hostPort": 32774,
                            "protocol": "tcp"
                        },
                        {
                            "bindIP": "0.0.0.0",
                            "containerPort": 9090,
                            "hostPort": 32773,
                            "protocol": "tcp"
                        }
                    ],
                    "networkInterfaces": [],
                    "healthStatus": "UNKNOWN",
                    "cpu": "1536",
                    "memory": "3584"
                }
            ],
            "cpu": "1536",
            "createdAt": 1603390576.188,
            "desiredStatus": "RUNNING",
            "group": "service:prism-api__advertising-prod",
            "healthStatus": "UNKNOWN",
            "lastStatus": "RUNNING",
            "launchType": "EC2",
            "memory": "3584",
            "overrides": {
                "containerOverrides": [
                    {
                        "name": "prism-api"
                    }
                ],
                "inferenceAcceleratorOverrides": []
            },
            "pullStartedAt": 1603390576.564,
            "pullStoppedAt": 1603390577.564,
            "startedAt": 1603390577.564,
            "startedBy": "ecs-svc/3925212241363435971",
            "tags": [],
            "taskArn": "arn:aws:ecs:us-east-1:12345678910:task/va-mle--prod/08e6004b550c4adc8d760e6ef8618482",
            "taskDefinitionArn": "arn:aws:ecs:us-east-1:12345678910:task-definition/prism-api__advertising-prod:11",
            "version": 2
        }
    ],
    "failures": []
}
## Inspect pod spec
kubectl describe pod ai-kafka-lag-reporting--production-burrow-695d887765-6g2mz

Name:         ai-kafka-lag-reporting--production-burrow-695d887765-6g2mz
Namespace:    monitoring
Priority:     0
Node:         ip-10-201-41-15.ec2.internal/10.201.41.15
Start Time:   Fri, 23 Oct 2020 06:18:23 -0700
Labels:       app.kubernetes.io/instance=ai-kafka-lag-reporting--production
              app.kubernetes.io/name=burrow
              pod-template-hash=695d887765
Annotations:  checksum/config: 76685e6b14d969203808ad9b123ce98882855ce11558a90291622c008cbb65f1
              checksum/templates: 2f6e14d9dc3289a56da3ee67666dff22aa865cbac57762a4efde12fd200a4437
              kubernetes.io/psp: eks.privileged
Status:       Running
IP:           10.201.38.236
IPs:
  IP:           10.201.38.236
Controlled By:  ReplicaSet/ai-kafka-lag-reporting--production-burrow-695d887765
Containers:
  burrow:
    Container ID:   docker://e4107e28b35f093f3f48ab2f80f0895971d325507cd499c0dba7dc636a3ba1f4
    Image:          ifoodhub/burrow:1.3.3
    Image ID:       docker-pullable://ifoodhub/burrow@sha256:ed9b8629983eddf496fc953fbe053db78370db594bd3cf1541c38c03c8b7b5b1
    Port:           8000/TCP
    Host Port:      0/TCP
    State:          Running
      Started:      Fri, 23 Oct 2020 06:18:27 -0700
    Ready:          True
    Restart Count:  0
    Liveness:       http-get http://:http/burrow/admin delay=0s timeout=1s period=10s #success=1 #failure=3
    Readiness:      http-get http://:http/burrow/admin delay=0s timeout=1s period=10s #success=1 #failure=3
    Environment:    <none>
    Mounts:
      /etc/burrow from config (rw)
      /etc/burrow/templates from templates (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-btxjt (ro)
Conditions:
  Type              Status
  Initialized       True
  Ready             True
  ContainersReady   True
  PodScheduled      True
Volumes:
  config:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      ai-kafka-lag-reporting--production-burrow
    Optional:  false
  templates:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      ai-kafka-lag-reporting--production-burrow-templates
    Optional:  false
  default-token-btxjt:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-btxjt
    Optional:    false
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     node.kubernetes.io/not-ready:NoExecute for 300s
                 node.kubernetes.io/unreachable:NoExecute for 300s
Events:          <none>

BASIC NAVIGATION - Check logs

### Inspect logs of a container from cluster va-mle--prod
# ¯\_(ツ)_/¯
ssh ubuntu@<instance>
docker ps
docker logs -f <container-id>

{"level":"warn","ts":1603459219.4788227,"msg":"unknown consumer","type":"module","coordinator":"storage","class":"inmemory","name":"default","worker":2,"cluster":"va-verity-kafka","consumer":"KMOffsetCache-kafka-manager--production-6dcb578fc-bnfpb","topic":"","partition":0,"topic_partition_count":0,"offset":0,"timestamp":0,"owner":"","client_id":"","request":"StorageFetchConsumer"}
{"level":"info","ts":1603459219.478872,"msg":"cluster or consumer not found","type":"module","coordinator":"evaluator","class":"caching","name":"default","cluster":"va-verity-kafka","consumer":"KMOffsetCache-kafka-manager--production-6dcb578fc-bnfpb","showall":false}
## Check pod logs
# ❤
kubectl logs -f ai-kafka-lag-reporting--production-burrow-695d887765-6g2mz

{"level":"warn","ts":1603459219.4788227,"msg":"unknown consumer","type":"module","coordinator":"storage","class":"inmemory","name":"default","worker":2,"cluster":"va-verity-kafka","consumer":"KMOffsetCache-kafka-manager--production-6dcb578fc-bnfpb","topic":"","partition":0,"topic_partition_count":0,"offset":0,"timestamp":0,"owner":"","client_id":"","request":"StorageFetchConsumer"}
{"level":"info","ts":1603459219.478872,"msg":"cluster or consumer not found","type":"module","coordinator":"evaluator","class":"caching","name":"default","cluster":"va-verity-kafka","consumer":"KMOffsetCache-kafka-manager--production-6dcb578fc-bnfpb","showall":false}

Deep-Dive

Tooling / helm / helmfile / Gitops

Deep dive - General tooling

~ Training / Development ~

HelmFILE is a wrapper on top of helm

Helmfile is what Terragrunt is to Terraform

Helm is a package manager for Kubernetes

Helm is your new ecs-cli

Kubernetes UIs - Blog Post 04/05/2020 by  

Deep dive - Helm - Introduction

Helm is a package manager for Kubernetes

Helm is your new ecs-cli...

  • A chart is a collection of files that describe a related set of Kubernetes resources.
     
  • A chart is made of Go templates
     
  • A single chart might be used to deploy something simple, like a memcached pod, or something complex, like a full web app stack with HTTP servers, databases, caches, and so on.
### Requirements: 
###   * Install helm > v3.0

helm create ops-talks
  Creating ops-talks
  
# Tree of the created chart
ops-talks
├── Chart.yaml
├── charts
├── templates
│   ├── NOTES.txt
│   ├── _helpers.tpl
│   ├── deployment.yaml
│   ├── hpa.yaml
│   ├── ingress.yaml
│   ├── service.yaml
│   ├── serviceaccount.yaml
│   └── tests
│       └── test-connection.yaml
└── values.yaml

3 directories, 10 files

What is a CHART ?

Deep dive - Helm - Open source Charts

$ helm install confluentinc/cp-helm-charts
$ helm install jenkins/jenkins
  • https://github.com/jenkinsci/helm-charts
  • https://github.com/confluentinc/cp-helm
  • ​https://github.com/helm/charts/
  • https://github.com/Lowess/helm-charts
$ helm install stable/atlantis
$ helm install stable/atlantis

Deep dive - Helm - TemplAte Hydrating

stable/atlantis
$ helm install stable/atlantis
  • configmap-config.yaml
  • configmap-repo-config.yaml
  • extra-manifests.yaml
  • ingress.yaml
  • secret-aws.yaml
  • secret-gitconfig.yaml
  • secret-service-account.yaml
  • secret-webhook.yaml
  • service.yaml
  • serviceaccount.yaml
  • statefulset.yaml

values.yaml

Deep dive - Helm - Values Overrides

stable/atlantis
$ helm install stable/atlantis

values.yaml (default)

# Replace this with your own repo whitelist:
orgWhitelist: bitbucket.org/gumgum/*
logLevel: "debug"

myvalues.yaml (overrides)

myvalues.yaml

merge

Deep dive - HELMfile

HELMFILE IS A WRAPPER ON TOP OF HELM

Helmfile is what Terragrunt is to Terraform...

Why ?

  • Helm is a great tool for templating and sharing K8s manifests...  However it can become quite cumbersome to install larger multi-tier applications or groups of applications across multiple Kubernetes clusters.
     
  • Give each Helm chart its own helmfile.yaml and include them recursively in a centralized helmfile.yaml.
     

  • Separate out environment specific values from general values. Often you’ll find while a Helm chart can take 50 different values, only a few actually differ between your environments.
     

  • As well as providing a set of values, either Environment specific or otherwise, you can also read Environment Variables, Execute scripts and read their output (Fetch a secret from AWS SSM)
     

  • Store remote state in git/s3/fileshare/etc in much the same way as Terraform does.

Deep dive - HELMfile - Layout

bases:
  - ../../environments.yaml

---

repositories:
  # Use Lowess (Florian Dambrine) OSS helm chart repo
  - name: lowess-helm
    url: https://lowess.github.io/helm-charts

templates:
  default: &default
    chart: "lowess-helm/karrot"
    missingFileHandler: Error
    namespace: "monitoring"
    labels: {}
    version: "0.1.3"
    wait: true
    installed: {{ and (env "KAFKA_LAG_REPORTING_INSTALLED" | default "true") }}

releases:
  - name: "ai-kafka-lag-reporting--{{ .Environment.Name }}"
    <<: *default
    values:
      - "./values/{{`{{ .Release.Name }}`}}.yaml"
helmfile.yaml
environments.yaml
releases
├── kafka-lag-reporting
│   ├── README.md
│   ├── helmfile.yaml
│   └── values
│       ├── ai-kafka-lag-reporting--production.yaml
│       ├── ai-kafka-lag-reporting--staging.yaml
│       └── kafka-lag-reporting--production.yaml
├── kafka-manager
│   ├── helmfile.yaml
│   └── values
│       └── kafka-manager--production.yaml
├── prometheus
│   ├── helmfile.yaml
│   └── values
│       ├── prometheus-mle--production.yaml
│       ├── prometheus-nlp--production.yaml
│       └── prometheus-verity--production.yaml
└── zoonavigator
    ├── helmfile.yaml
    └── values
        └── verity-zoonavigator--production.yaml

Deep dive - Gitops

Principles of GitOpS

  • #1 The entire system described declaratively

  • #2 The canonical desired system state versioned in Git

  • #3 Approved changes that can be automatically applied to the system

  • #4 Software agents to ensure correctness and alert on divergence.

CHEATSHEET

Ops

 TALKS

Knowledge worth sharing

By Florian

Ops-Talks #03

By Florian Dambrine

Ops-Talks #03

OpsTalks #03 - K8s & ECS

  • 1,302