3.15. Executing a Remote Job

Procedure

1. Navigate to Hosts > All Hosts and select the target hosts on which you want to execute a remote job. You can use the search field to filter the host list.
2. From the Select Action list, select Schedule Remote Job.
3. On the Job invocation page, define the main job settings:
4. Select the Job category and the Job template you want to use.
5. Optional: Select a stored search string in the Bookmark list to specify the target hosts.
6. Optional: Further limit the targeted hosts by entering a Search query. The Resolves to line displays the number of hosts affected by your query. Use the refresh button to recalculate the number after changing the query. The preview icon lists the targeted hosts.
7. The remaining settings depend on the selected job template. See 「Creating a Job Template:」 for information on adding custom parameters to a template.

8. Optional: To configure advanced settings for the job, click Display advanced fields. Some of the advanced settings depend on the job template, the following settings are general:

   • Effective user defines the user for executing the job, by default it is the SSH user.
   • Concurrency level defines the maximum number of jobs executed at once, which can prevent overload of systems' resources in a case of executing the job on a large number of hosts.
   • Timeout to kill defines time interval in seconds after which the job should be killed, if it is not finished already. A task which could not be started during the defined interval, for example, if the previous task took too long to finish, is canceled.
   • Type of query defines when the search query is evaluated. This helps to keep the query up to date for scheduled tasks.

   • Execution ordering determines the order in which the job is executed on hosts: alphabetical or randomized.

     Concurrency level and Timeout to kill settings enable you to tailor job execution to fit your infrastructure hardware and needs.

9. To run the job immediately, ensure that Schedule is set to Execute now. You can also define a one-time future job, or set up a recurring job. For recurring tasks, you can define start and end dates, number and frequency of runs. You can also use cron syntax to define repetition. For more information about cron, see the Automating System Tasks section of the Red Hat Enterprise Linux 7 System Administrator’s Guide.
10. Click Submit. This displays the Job Overview page, and when the job completes, also displays the status of the job.

1. Find the ID of the job template you want to use:

   # hammer job-template list

2. Show the template details to see parameters required by your template:

   # hammer job-template info --id template_ID

3. Execute a remote job with custom parameters:

   # hammer job-invocation create \
   --job-template "template_name" \
   --inputs key1="value",key2="value",... \
   --search-query "query"

   Replace query with the filter expression that defines hosts, for example "name ~ rex01". For more information about executing remote commands with hammer, enter hammer job-template --help and hammer job-invocation --help.