Target ranges and/or dynamic target lists

[pakalee]

Is there a way to define, or expand, targets as a range, like "n[1:500].cluster.hpc"?

Related, can you build and use target lists using the dynamic-target approach?

[umputun]

no range syntax in spot, neither in targets nor in the inventory. For a range, generate the inventory and run against the group. Hosts in one group run in parallel with -c:

{ echo "groups:"; echo "  hpc:"; for i in $(seq 1 500); do echo "    - {host: n$i.cluster.hpc}"; done; } > inventory.yml
spot -i inventory.yml -t hpc -c 50

-i also accepts a URL, so the list can come from an HTTP endpoint.

a dynamic target resolves to one target name, so a list of hosts in the variable won't work. The name can be a group, tag or playbook target, and spot expands it to all its hosts:

tasks:
  - name: pick group
    targets: ["default"]
    options: {local: true}
    commands:
      - name: set group
        script: export grp=hpc
  - name: run on group
    targets: ["$grp"]
    commands:
      - name: show host
        script: hostname