open-nomad/website/source/docs/job-specification/group.html.md

107 lines
2.6 KiB
Markdown
Raw Normal View History

---
layout: "docs"
page_title: "group Stanza - Job Specification"
sidebar_current: "docs-job-specification-group"
description: |-
The "group" stanza defines a series of tasks that should be co-located on the
same Nomad client. Any task within a group will be placed on the same client.
---
# `group` Stanza
<table class="table table-bordered table-striped">
<tr>
<th width="120">Placement</th>
<td>
<code>job -> **group**</code>
</td>
</tr>
</table>
The `group` stanza defines a series of tasks that should be co-located on the
same Nomad client. Any [task][] within a group will be placed on the same
client.
```hcl
job "docs" {
group "example" {
# ...
}
}
```
## `group` Parameters
2016-10-28 03:01:11 +00:00
- `constraint` <code>([Constraint][]: nil)</code> -
This can be provided multiple times to define additional constraints.
- `count` `(int: 1)` - Specifies the number of the task groups that should
be running under this group. This value must be non-negative.
2016-10-28 03:01:11 +00:00
- `meta` <code>([Meta][]: nil)</code> - Specifies a key-value map that annotates
with user-defined metadata.
- `restart` <code>([Restart][]: nil)</code> - Specifies the restart policy for
all tasks in this group. If omitted, a default policy exists for each job
2016-10-28 03:01:11 +00:00
type, which can be found in the [restart stanza documentation][restart].
- `task` <code>([Task][]: required)</code> - Specifies one or more tasks to run
within this group. This can be specified multiple times, to add a task as part
of the group.
## `group` Examples
The following examples only show the `group` stanzas. Remember that the `group`
Remember that the `group` stanza is only valid in the placements listed above.
### Specifying Count
This example specifies that 5 instances of the tasks within this group should be
running:
```hcl
group "example" {
count = 5
}
```
2016-10-28 03:01:11 +00:00
### Tasks with Constraint
2016-10-28 03:01:11 +00:00
This example shows two abbreviated tasks with a constraint on the group. This
will restrict the tasks to 64-bit operating systems.
```hcl
group "example" {
constraint {
attribute = "${attr.arch}"
value = "amd64"
}
2016-10-28 03:01:11 +00:00
task "cache" {
# ...
}
task "server" {
# ...
}
}
```
### Metadata
This example show arbitrary user-defined metadata on the group:
```hcl
group "example" {
meta {
"my-key" = "my-value"
}
}
```
[task]: /docs/job-specification/task.html "Nomad task Specification"
[job]: /docs/job-specification/job.html "Nomad job Specification"
[constraint]: /docs/job-specification/constraint.html "Nomad constraint Specification"
[meta]: /docs/job-specification/meta.html "Nomad meta Specification"
[restart]: /docs/job-specification/restart.html "Nomad restart Specification"