Tags let you categorize EMR clusters by purpose, owner, or environment — making it easier to identify and manage resources across your account. For example, tag clusters to distinguish production from testing environments, or to track which team owns each cluster.
You can add up to 20 tags to a single cluster, either when you create the cluster or after.
Manage tags on ECS instances through the EMR console, not the ECS console. If you update tags on an EMR cluster, the tags on its ECS instances are also updated in the ECS console. However, changes made in the ECS console do not sync back to the EMR cluster. If the tag count on an ECS instance reaches the upper limit, you can no longer add tags to the cluster.
System tags
When you create an E-MapReduce (EMR) cluster, two system tags are automatically added to each Elastic Compute Service (ECS) instance in the cluster. These tags identify which cluster the instance belongs to and its role in the cluster.
To view system tags, log on to the Alibaba Cloud ECS console and hover over the tag icon of an ECS instance on the Instances page.
For example, an ECS instance may have these system tags:
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acs:emr:clusterId=c-59efc7546480**** -
acs:emr:nodeGroupType=CORE
In this example, the ECS instance is a core node of the EMR cluster with ID c-59efc7546480****.
Limitations
| Constraint | Limit |
|---|---|
| Tags per cluster | 20 |
| Tag key length | Up to 128 characters, cannot be empty |
| Tag value length | Up to 128 characters, can be empty |
| Forbidden prefixes | Cannot start with aliyun or acs: |
| Forbidden strings | Cannot contain http:// or https:// |
| Tag key uniqueness | A tag key must be unique within a cluster. Adding a tag with a duplicate key replaces the existing tag. For example, if city/shanghai is on a cluster and you add city/newyork, the city/shanghai tag is removed automatically. |
| Tag scope | Tag information is not shared across regions. Tags created in the China (Hangzhou) region are not visible in the China (Shanghai) region. |
When you detach a tag, it is deleted if it is not attached to any other resources. You can still view and reattach historical tags.
Add tags when creating a cluster
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Log on to the EMR console. In the left-side navigation pane, click EMR on ECS.
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In the top menu bar, select the target region and resource group.
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Click Create Cluster. On the Basic Configuration page, go to the Advanced Settings section and click Add Tag in the Tags row. For more information, see Create a cluster.
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Select an existing tag key and tag value to attach a tag, or enter a new tag key and tag value to create and attach a tag.
Manage tags on an existing cluster
Add a new tag
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On the EMR on ECS page, find the target cluster. In the Actions column, choose
> Edit Tag. -
In the Edit Tag dialog box, click Add New Tag.
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Enter a Key and a Value, then click OK.
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Click OK.
Attach an existing tag
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On the EMR on ECS page, find the target cluster. In the Actions column, choose
> Edit Tag. -
In the Edit Tag dialog box, click Add Existing Tag.
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Select a Tag Key and a Tag Value, then click OK.
Detach a tag
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On the EMR on ECS page, find the target cluster. In the Actions column, choose
> Edit Tag. -
In the Edit Tag dialog box, click the
icon next to the tag you want to detach.
A detached tag is deleted if it is not attached to any other resources. Historical tags can still be viewed and reattached.
Search for clusters by tag
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Log on to the EMR console. In the left-side navigation pane, click EMR on ECS.
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Select a tag key and a tag value from the Search by tag drop-down list. Clusters matching the selected tag appear in the list. If you select only a tag key without a tag value, all clusters with that tag key are displayed.