Build EC2 placement group configurations for cluster, spread, and partition strategies with instance requirements.
Build EC2 placement group configurations for cluster, spread, and partition strategies with instance requirements.
Required Fields
GroupNameStrategyOutput will appear here...Build an EC2 placement group using one of three mutually exclusive strategies: cluster (packs instances close together on the same low-latency network fabric, ideal for tightly-coupled HPC/MPI workloads but with zero built-in hardware failure isolation), spread (each instance on genuinely distinct underlying hardware, max 7 instances per group per AZ, for maximizing availability of a small number of critical instances), or partition (logical partitions with independent failure domains, up to 7 per AZ, for distributed systems like HDFS/Cassandra/Kafka that already handle partition-level failure at the application layer). Picking cluster for a workload that actually needs spread's failure isolation (or vice versa) is a common and costly mistake since the strategy can't be changed on an existing placement group, only a new group with a fresh strategy.
Placement group strategy is immutable after creation, get the choice right up front based on the actual workload characteristic that matters (latency vs. availability vs. logical partitioning), a wrong initial choice means recreating the group and migrating instances, not a quick fix.
Cluster placement's main value (low inter-instance latency) is wasted on a workload that isn't actually network-communication-bound, don't default to cluster placement just because it sounds like the 'performance' option, check whether your workload's bottleneck is actually inter-node network latency first.
Spread placement's 7-instances-per-AZ-per-group cap is a hard architectural constraint, not a soft quota, a workload needing more than 7 genuinely hardware-isolated instances per AZ needs multiple spread placement groups or a different isolation strategy, not a support ticket asking for a limit increase.
The builder validates that GroupName and Strategy resolve before accepting the JSON as a valid CreatePlacementGroup request, the two fields EC2 requires; PartitionCount, SpreadLevel, and instance requirements are validated as well-formed JSON but their applicability depends on which Strategy was chosen (PartitionCount is only meaningful for partition strategy, for instance), a mismatch there is a semantic error the tool doesn't catch, only the live API would reject it.
Was this tool helpful?
Disclaimer: This tool runs entirely in your browser. No data is sent to our servers. Always verify outputs before using them in production. AWS, Azure, and GCP are trademarks of their respective owners.