Living the Nomadic life - Nic Jackson
•
3 likes•1,796 views
This document provides an overview and agenda for a presentation on Nomad, an open source cluster scheduler created by HashiCorp. The presentation will cover Nomad fundamentals including architecture, job configuration, and scheduling. It will also demonstrate Nomad's ability to schedule a million containers across thousands of hosts on Google Cloud Platform.
Report
Share
Living the Nomadic life - Nic Jackson
- 5. 5 FOUNDED 2012 by Mitchell Hashimoto and Armon Dadgar MISSION We enable organizations to provision, secure, and run any infrastructure for any application INVESTORS Mayfield Fund, GGV Capital, Redpoint and True Ventures KEY PRODUCTS Vagrant, Packer, Terraform, Vault, Nomad, Consul COMPANY OVERVIEW
- 6. 6 OSS TO ENTERPRISE SOFTWARE INNOVATORS TECHNOLOGY PARTNERS
- 10. Schedulers map a set of work to a set of resources
- 13. 13 SCHEDULERS IN THE WILD 13 Type Work Resources CPU Scheduler Threads Physical Cores EC2 / Nova Virtual Machines Hypervisors Hadoop YARN MapReduce Jobs Client Nodes Cluster Scheduler Applications Machines
- 14. 14 SCHEDULER ADVANTAGES 14 Higher Resource Utilization Decouple Work from Resources Better Quality of Service
- 15. 15 SCHEDULER ADVANTAGES 15 Bin Packing Over-Subscription Job Queueing Higher Resource Utilization Decouple Work from Resources Better Quality of Service
- 16. 16 SCHEDULER ADVANTAGES 16 Abstraction API Contracts Standardization Higher Resource Utilization Decouple Work from Resources Better Quality of Service
- 17. 17 SCHEDULER ADVANTAGES 17 Priorities Resource Isolation Pre-emption Higher Resource Utilization Decouple Work from Resources Better Quality of Service
- 18. 18 NOT A NEW CONCEPT 18
- 20. NOMAD OVERVIEW
- 21. 21 NOMAD DESIGN PRINCIPLES 21HashiCorp confidential do not distribute Integrated scheduler and cluster manager Distributed, shared state, optimistically concurrent Agent-based, client/server No dependencies
- 22. 22 NOMAD CHARACTERISTICS 22HashiCorp confidential do not distribute Multi-datacenter and multi-region Highly performant and highly available Hybrid workloads with multiple schedulers and drivers Seamlessly integrates with HashiCorp ecosystem
- 24. 24 SINGLE REGION DEPLOYMENT 24 SERVER SERVER SERVER CLIENT CLIENT CLIENTDC1 DC2 DC3 FOLLOWER LEADER FOLLOWER REPLICATION FORWARDING REPLICATION FORWARDING RPC RPC RPC
- 25. 25 MULTI REGION DEPLOYMENT 25 SERVER SERVER SERVER FOLLOWER LEADER FOLLOWER REPLICATION FORWARDING REPLICATION REGION B GOSSIP REPLICATION REPLICATION FORWARDING REGION FORWARDING REGION A SERVER FOLLOWER SERVER SERVER LEADER FOLLOWER
- 26. 26 SERVER ARCHITECTURE 26 Omega Class Scheduler Pluggable Logic Internal Coordination and State Multi-Region / Multi-Datacenter
- 27. 27 CLIENT ARCHITECTURE 27 Broad OS Support Host Fingerprinting Pluggable Drivers Job restarts and lifecycle management
- 28. 28 CLIENT DRIVERS 28 Containerized Docker rkt Windows Server Containers Virtualized Qemu / KVM Hyper-V Xen Standalone Java Jar C# Static Binaries
- 29. 29 CLIENT FINGERPRINTING 29 Type Examples Operating System Kernel, OS, Version Hardware CPU, Memory, Disk Apps (Capabilities) Docker, Java, Consul Environment AWS, GCE
- 31. 31 JOB FILE 31 Declarative Scheduler, driver, and resource needs Lifecycle behavior Constraints Versioned
- 32. 32 redis.nomad JOB FILE job "redis" { datacenters = ["us-east-1"] task "redis" { driver = "docker" config { image = "redis:v13" } resources { cpu = 500 # Mhz memory = 256 # MB network { mbits = 10 dynamic_ports = ["redis"] } } } }
- 33. 33 redis.nomad JOB FILE: TASK GROUPS job "app" { group "app" { task "redis" { # ... } task "app" { # ... } } }
- 34. 34 redis.nomad JOB FILE: CONSTRAINTS job "redis" { constraint { attribute = "${attr.kernel.version}" operator = "version" value = "> 3.19" } constraint { attribute = "${attr.platform.aws.instance-type}" value = "p2.16xlarge" } task "redis" { # ... } }
- 35. 35 redis.nomad JOB FILE: CONSUL SERVICE DISCOVERY job "redis" { task "redis" { # ... service { port = “redis” check { type = “tcp” interval = “10s” } } } }
- 36. 36 redis.nomad JOB FILE: CONSUL CONFIGURATION job "redis" { task "redis" { # ... template { data = <<EOH bind_port: {{ env "NOMAD_PORT_db" }} scratch_dir: {{ env "NOMAD_TASK_DIR" }} service_key: {{ key "service/my-key" }} EOH destination = "local/file.yml" } } }
- 37. 37 redis.nomad JOB FILE: VAULT INTEGRATION job "redis" { task "redis" { # ... template { data = <<EOH {{ with secret "secret/credentials" }} username: {{ .Data.username }} password: {{ .Data.password }} {{ end }} EOH destination = "local/file.yml" } } }
- 38. 38 redis.nomad JOB FILE: PARAMETERIZED job "encode" { type = "batch" parameterized { payload = "required" meta_required = ["s3-input", "s3-output", ...] } # ... task "ffmpeg" { driver = "exec" config { command = "ffmpeg" # When dispatched, the payload is written to a file that is then # read by the created task upon startup args = ["-config=${NOMAD_TASK_DIR}/config.json"] # ... }
- 39. 39 $ nomad job dispatch encode video-config.json $ $ cat video-config.json { "s3-input": "https://s3-us-west-1.com/video-bucket/cb31dabb1", "s3-output": "https://s3-us-west-1.com/video-bucket/a149adbe3", "input-codec": "mp4", "output-codec": "webm", "quality": "1080p" } Text JOB FILE: PARAMETERIZED
- 41. Why Multi-Cloud? • High Availability • Redundancy • Burstable Workload • Cloud Migration • Because we can
- 42. 42 CONSUL NOMAD SERVER LEADER SERVER FOLLOWER SERVER LEADER SERVER FOLLOWER SERVER FOLLOWER SERVER FOLLOWER NODE A NODE B GOOGLE CLOUD NATS CLOUD MESSAGING REPLICATION FORWARDING REPLICATION FORWARDING REPLICATION FORWARDING REPLICATION FORWARDING LOAD BALANCER LOAD BALANCER CONSUL NOMAD SERVER LEADER SERVER FOLLOWER SERVER LEADER SERVER FOLLOWER SERVER FOLLOWER SERVER FOLLOWER NODE A NODE B AWS REPLICATION FORWARDING REPLICATION FORWARDING REPLICATION FORWARDING REPLICATION FORWARDING LOAD BALANCER REGION FORWARDING (VPN) REGION FORWARDING (VPN)
- 43. NOMAD SCHEDULING
- 44. 44 SCHEDULING 44 Schedulers process evaluations and generate allocation plans. Placement is determined using the relevant scheduler. Scheduling involves feasibility checking and ranking. Feasibility filters out nodes missing necessary drivers and those failing the specified constraints. Ranking score feasible nodes to find the best fit (bin packing).
- 45. 45 SCHEDULER TYPES 45HashiCorp confidential do not distribute Service Long-running applications and services Batch Short-lived data processing jobs (benefit from fast placement) System Lower level jobs that run on all clients (logging, monitoring)
- 46. 46 $ nomad plan example.nomad + Job: "example" + Task Group: "cache" (1 create) + Task: "redis" (forces create) Scheduler dry-run: - All tasks successfully allocated. $ Text SCHEDULING: PLAN
- 47. 47 $ nomad plan example.nomad.java + Job: "example" + Task Group: "web" (1 create) + Task: "tomcat" (forces create) Scheduler dry-run: - WARNING: Failed to place all allocations. Task Group "web" (failed to place 1 allocation): * Constraint "missing drivers" filtered 2 nodes $ Text SCHEDULING: PLAN
- 48. 48 $ nomad run example.nomad ==> Monitoring evaluation "4b8b7779" Evaluation triggered by job "example" Allocation "38720b8e" created: node "ec2f0830", group "cache" Evaluation status changed: "pending" -> "complete" ==> Evaluation "4b8b7779" finished with status "complete" $ Text SCHEDULING: RUN
- 49. 49 $ nomad run -region=gcp events.nomad ==> Monitoring evaluation "e2a8dfe6" !On branch master Evaluation triggered by job "events" !Your branch is up-to-date with 'origin/master'. Allocation "6615b39f" modified: node "0d6a6103", group "pubsub" !nothing to commit, working tree clean Evaluation status changed: "pending" -> "complete" ! ==> Evaluation "e2a8dfe6" finished with status "complete" $ Text SCHEDULING: RUN DIFFERENT REGION
- 50. 50 $ nomad status example ID = example Name = example Type = service Priority = 50 Datacenters = us-west-1 Status = running Summary Task Group Queued Starting Running Failed Complete Lost cache 0 0 1 0 0 0 Allocations ID Eval ID Node ID Task Group Desired Status Created At 38720b8e 4b8b7779 ec2f0830 cache run running 04/26/17 ... $ Text SCHEDULING: STATUS
- 51. DEMO!
- 52. Nomad Million Container Challenge 1,000 Jobs 1,000 Tasks per Job 5,000 Hosts on GCE 1,000,000 Containers
- 54. 54 MILLION CONTAINER CHALLENGE 54 – Bill Gates 640 KB ought to be enough for anybody. “
- 55. 55 REAL WORLD SCALE 55 2nd Largest Hedge Fund 18K Cores 5 Hours 2,200 Containers/ second