Tags are used to label clusters. You can use tags to identify and manage your cluster resources. You can add tags when you create a cluster. You can also add tags on the Cluster Overview page of a created cluster. You can add up to 20 tags to a single cluster. This topic describes how to add, remove, and view tags and how to use tags to search for clusters.

Background information

An E-MapReduce (EMR) cluster contains multiple Elastic Compute Service (ECS) instances. When you create an EMR cluster, two system tags are automatically added to each ECS instance in the cluster. To identify the cluster to which an ECS instance belongs and to identify the role of the ECS instance in the cluster, perform the following steps: Log on to the Alibaba Cloud ECS console and move the pointer over the tag icon of an ECS instance on the Instances page. View system tags
For example, an ECS instance has the following system tags:
  • acs:emr:clusterId=C-A510C93EA117****
  • acs:emr:hostGroupType=CORE
In this example, the ECS instance is a core node of an EMR cluster whose ID is C-A510C93EA117****.

Precautions

  • If you update the tags of an EMR cluster, the tags of the ECS instances in the cluster are also updated in the ECS console.
  • If you update the tags of ECS instances in the ECS console, the tags of the EMR cluster to which the ECS instances belong are not updated. To make sure that the tags of ECS instances are consistent with the tags of the EMR cluster, we recommend that you do not update the tags of ECS instances in the ECS console. If the number of tags of an ECS instance in a cluster reaches the upper limit, you can no longer create tags for the cluster.
  • Tag information is not shared across regions.

    For example, tags that are created in the China (Hangzhou) region are invisible in the China (Shanghai) region.

  • You can add up to 20 tags to a cluster. If the number of tags that are added to a cluster exceeds the upper limit, you must remove some of the tags before you add new tags.

Add a new tag or an existing tag when you create a cluster

  1. Log on to the Alibaba Cloud EMR console.
  2. In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
  3. Click Cluster Wizard in the Clusters section. In the Advanced Settings section of the Basic Settings step, find Tag and click + Add.
    For more information about how to create a cluster, see Create a cluster.
  4. In the Create/Bind Tag dialog box, select an existing tag key or enter a new tag key for Tag Key.
    If you select an existing tag key, you can add an existing tag. If you enter a new tag key, you can create a tag and then add the tag. Create/Bind Tag
    Note Each tag consists of a key-value pair. Tag keys and tag values have the following limits:
    • A tag key cannot be empty and can be up to 128 characters in length. A tag value can be empty and can be up to 128 characters in length.
    • Tag keys and tag values cannot start with aliyun or acs: and cannot contain http:// or https://.
    • A tag key must be unique in a cluster. For example, the city/shanghai tag is added to a cluster. If the city/newyork tag is then added to the cluster, the city/shanghai tag is automatically removed.
  5. Click Confirm.
    Confirm the tag to be added.
  6. Click Confirm.
    The tag is added.

Use tags to search for clusters

On the Cluster Management page, search for a cluster by using a tag key or tag value.

  1. Go to the Cluster Management page.
    1. Log on to the Alibaba Cloud EMR console.
    2. In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
    3. Click the Cluster Management tab.
  2. On the Cluster Management page, click Tag and select a tag key.
    If you do not select a tag value, all clusters to which the tag key is added are displayed.
  3. Click Search next to Tag.
    All the clusters that meet the search condition are displayed.

Manage the tags of an existing cluster

You can add, remove, or view the tags of an existing cluster.

  1. Go to the Cluster Overview page of your cluster.
    1. Log on to the Alibaba Cloud EMR console.
    2. In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
    3. Click the Cluster Management tab.
    4. Find the cluster whose tags you want to manage and click Details in the Actions column.
  2. On the Cluster Overview page, click Edit Tag in the Cluster Info section.
  3. In the Edit Tag dialog box, perform the following steps:
    • Add a new tag.
      1. Click Add Tag in the lower-left corner.
      2. In the Edit Tag dialog box, specify Tag Key and Tag Value.
      3. Click Confirm.
      4. Click Confirm.
    • Add an existing tag.
      1. Click Existing Tags in the lower-left corner.
      2. Select an existing tag key and the tag value that matches the tag key.
      3. Click Confirm.
    • Remove a tag.
      Click the Remove icon next to a tag to remove this tag.
      Note After you remove a tag from a cluster, the system automatically deletes the tag if the tag is not added to other clusters.