Intro to Scheduling with Nomad

Karl Bielefeldt

Agenda

• What is a scheduler?
• Nomad compared to other schedulers
• Demo

[servers:children]
DC1
DC2

[DC1]
10.1.1.101 node_num=1 roles='["osa-cp", "dnsmasq", "zookeeper", "cassandra", "kafka"]'
10.1.1.102 node_num=2 roles='["pmaa"]'
10.1.1.103 node_num=3 roles='["osa-cp", "dnsmasq", "zookeeper", "cassandra", "kafka"]'

[DC1:vars]
node_availability=available

[DC2]
10.1.2.104 node_num=4 roles='["osa-cp", "dnsmasq", "zookeeper", "cassandra", "kafka"]'
10.1.2.105 node_num=5 roles='["pmaa"]'
10.1.2.106 node_num=6 roles='["osa-cp", "dnsmasq", "zookeeper", "cassandra", "kafka"]'

[DC2:vars]
node_availability=unavailable

[admin]
localhost ansible_connection=local

Primary resources managed by schedulers:

• Processes
• Docker containers
• Virtual Machines

Secondary resources managed by schedulers:

• Secrets
• Service Discovery
• Storage
• Networking
• Logging
• Access Control
• Configuration

What makes Nomad unique?

• Unix philosophy
• Cross-platform and not just docker
• Operationally simple
• Easy multi-datacenter
• Gradual migration path
• Bin packing
• Plan

Demo