Nodes targeting

Running a task on a single node

The basic syntax for running a task is:

jack run <node_name> <plugin.task> [arguments...]

Example:

jack run node1 health.ping

node1

→ output:
    true

Targeting methods overview

Jackadi provides several ways to target multiple nodes:

1. Single node targeting

Target a specific node by name:

jack run -t node1 example.task1

2. List-based targeting

Target multiple specific nodes:

jack run -l "node1,node2,node3" example.task1

3. Pattern-based targeting

Glob Patterns (default):

jack run -g "worker-*" example.task1
jack run "web-*" example.task1  # -g is default

Regular Expressions:

jack run -e "node[0-9]+" example.task1
jack run -e "^(web|api)-server-[0-9]{2}$" example.task1

4. Query targeting

The most advanced targeting method using hostname and/or specs:

Exact match

The operator for an exact match is ==.

jack run -q "id==hostname1" example.task1

List of nodes

The operator for a list is ==. The elements in the list are separated by a comma.

jack run -q "id==node1,node2" example.task1

Glob pattern

The operator for a glob pattern is =~.

jack run -q "id=~node*" example.task1

Regex pattern

The operator for regex filtering is =~, followed by /your_regex/.

jack run -q "id=~/^node.*$/" example.task1

Logical operators

You can combine multiple filters together using AND and OR.

The order of execution follows standard binary/mathematical logic: AND operations are processed before OR.

jack run -q "id==node1 AND specs.dev.hardware.Vendor==Lenovo" example.task1
jack run -q "id==node1 OR specs.dev.hardware.Type==Laptop" example.task1

Using nested spec

When the used spec is nested, like a map or a struct, you can access to a specific leaf using ..

jack run -q "specs.system.os.kernel.version=~'6.17.*'" kernel-specific.task

You can also access to an element of a list:

jack run -q "specs.system.network.interfaces[0].status==up" network.configure

4. Target from a file

You can import a list of target from a file (one node per line).

node1
node2
node3

jack run -f ./nodes.txt cmd.run "pwd"

Execute plugins as standalone binaries

Plugins can be executed directly from the terminal without Jackadi, see Standalone executable.