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    E-MapReduce:Add nodes to a deployment set

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    E-MapReduce:Add nodes to a deployment set

    Last Updated:Mar 26, 2026

    When a physical server fails, all EMR cluster nodes on that server go down together. A deployment set, provided by Elastic Compute Service (ECS), solves this by controlling how instances are distributed across physical servers — so a single hardware failure takes down at most one node per server, not a group.

    This topic describes how to enable Add to Deployment Set when creating a cluster or adding a node group, and how to view the resulting deployment set.

    Supported cluster types and node groups

    Add to Deployment Set is available only for the following:

    • Cluster types: DataLake, Dataflow, OLAP, DataServing, and custom

    • Node group types: Master and core node groups only. Task node groups are not eligible.

    Deployment strategies

    Some instance families support only specific strategies. To query which instance families support a given strategy, call the DescribeDeploymentSetSupportedInstanceTypeFamily operation.

    Instance families supported by high availability and high availability group strategies:

    • g8y, g7se, g7a, g7, g7t, g7ne, g6, g6e, g6a, g6h, g5, g5ne, sn2ne, sn2, and sn1, sn2, and sn1

    • c8y, c7se, c7, c7t, c7a, c6, c6a, c6e, c5, ic5, and sn1ne

    • r8y, r7, r7se, r7t, r7a, r6, r6e, r6a, re6, re6p, r5, re4, se1ne, and se1

    • hfc7, hfg7, hfr7, hfc6, hfg6, hfr6, hfc5, and hfg5

    • d3c, d2s, d2c, d1, d1ne, d1-c14d3, and d1-c8d3

    • i3g, i3, i2, i2g, i2ne, i2gne, and i1

    • ebmg5, sccgn6, scch5, sccg5, scch5s, and sccg5s

    • t6, xn4, mn4, n4, e4, n2, and n1n2, and n1

    • gn6i

    Instance families supported by low latency strategy:

    • g8a and g8y

    • c8a and c8y

    • r8a and r8y

    Limits and planning considerations

    Review these constraints before enabling Add to Deployment Set, as some cannot be changed after the cluster is created.

    Constraint Detail
    20-instance cap per deployment set A deployment set holds up to 20 ECS instances. Enable with caution if your node group may grow past this threshold.
    Cannot be disabled after cluster creation Once enabled for a node group, Add to Deployment Set cannot be turned off. Plan your deployment strategy before creating the cluster.
    Deployment set released with the cluster When a cluster is released, its associated deployment set is also released automatically. Do not manually add ECS instances to the deployment set created by EMR.

    Recommendations

    • Core nodes with local HDFS: If your cluster uses local HDFS and core nodes belong to a big data instance family or an instance family with local SSDs, add the core node group to a deployment set. Distributing replicated data blocks across physical servers protects against data loss when a server fails.

    • High Service Availability enabled: If you enable High Service Availability when creating a cluster, master nodes are automatically added to a deployment set by default. You do not need to configure this separately for master nodes.

    • Applies to all nodes in the group: Enabling Add to Deployment Set applies to all current and future nodes in the node group, including nodes added after the cluster is created.

    Enable Add to Deployment Set when creating a cluster

    1. Log on to the EMR console.

    2. In the left-side navigation pane, click EMR on ECS.

    3. In the top navigation bar, select the region and resource group for your cluster. and select a resource group based on your business requirements and select a resource group based on your business requirements

    4. Click Create Cluster.

    5. In the Hardware Configuration step, locate the master or core node group and turn on Add to Deployment Set. All nodes in the node group — including nodes added after cluster creation — are added to the deployment set. For full cluster creation parameters, see Create a cluster.

      Add to Deployment Set toggle in Hardware Configuration step

    Enable Add to Deployment Set when adding a node group

    The Add to Deployment Set option is available for core node groups when you add a node group to an existing cluster.

    1. Log on to the EMR console.

    2. In the left-side navigation pane, click EMR on ECS.

    3. In the top navigation bar, select the region and resource group where your cluster resides.

    4. Find the target cluster and click Nodes in the Actions column.

    5. On the Nodes tab, click Add Node Group.

    6. In the Add Node Group panel, configure the parameters and turn on Add to Deployment Set. All nodes in the node group — including nodes added after the node group is created — are added to the deployment set. For node group parameters, see the "Create a node group" section in Manage node groups.

      Add to Deployment Set toggle in Add Node Group panel

    View the deployment set

    After enabling Add to Deployment Set, view the deployment set in the ECS console. The deployment set is named emr-${clusterId}-default.

    1. Log on to the ECS console.

    2. In the left-side navigation pane, choose Deployment & Elasticity > icon1 > Deployment Sets.

    3. In the top navigation bar, select the region and resource group. 地域

    4. On the Deployment Sets page, find the deployment set named emr-${clusterId}-default.

      Important

      Do not modify the deployment set created by EMR. Modifying it may cause your cluster to stop functioning normally.

      Deployment set details page

    What's next

    For a complete overview of deployment set concepts, strategies, and limits in ECS, see Overview.