Kafka Streams Groups Tool

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Use kafka-streams-groups.sh to manage Streams groups for the Streams Rebalance Protocol (KIP‑1071): list and describe groups, inspect members and offsets/lag, reset or delete offsets for input topics, and delete groups (optionally including internal topics).

Overview

A Streams group is a broker‑coordinated group type for Kafka Streams that uses Streams‑specific RPCs and metadata, distinct from classic consumer groups. The CLI surfaces Streams‑specific states, assignments, and input‑topic offsets to simplify visibility and administration.

Use with care: Mutating operations (offset resets/deletes, group deletion) affect how applications will reprocess data when restarted. Always preview with --dry-run before executing and ensure application instances are stopped/inactive and the group is empty before executing the command.

What the Streams Groups tool does

  • List Streams groups across a cluster and display or filter by group state (Empty, Not Ready, Assigning, Reconciling, Stable, Dead).
  • Describe a Streams group and show:
    • Group state, group epoch, target assignment epoch (with --state, --verbose for additional details).
    • Per‑member info such as epochs, current vs target assignments, and whether a member still uses the classic protocol (with --members and --verbose).
    • Input‑topic offsets and lag (with --offsets), to understand how far behind processing is.
  • Reset input‑topic offsets for a Streams group to control reprocessing boundaries using precise specifiers (earliest, latest, to‑offset, to‑datetime, by‑duration, shift‑by, from‑file). Requires --dry-run or --execute and inactive instances.
  • Delete offsets for input topics to force re‑consumption on next start.
  • Delete a Streams group to clean up broker‑side Streams metadata (offsets, topology, assignments). Optionally delete all, or a subset of, internal topics at the same time using --internal-topics.

Usage

The script is located in bin/kafka-streams-groups.sh and connects to your cluster via --bootstrap-server. For secured clusters, pass AdminClient properties using --command-config.

$ kafka-streams-groups.sh --bootstrap-server <host:port> [COMMAND] [OPTIONS]

Note: kafka-streams-groups.sh complements the Streams Admin API for Streams groups. The CLI exposes list/describe/delete operations and offset management similar in spirit to consumer-group tools, but tailored to Streams groups defined in KIP‑1071.

Commands

List Streams groups

Discovering groups

# List all Streams groups
kafka-streams-groups.sh --bootstrap-server localhost:9092 --list

Describe Streams groups

Inspecting group’s state, members, and lag

# Describe a group: state + epochs
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --describe --group my-streams-app --state --verbose

# Describe a group: members (assignments vs target, classic/streams)
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --describe --group my-streams-app --members --verbose

# Describe a group: input-topic offsets and lag
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --describe --group my-streams-app --offsets

Reset input-topic offsets (preview, then apply)

Ensure all application instances are stopped/inactive. Always preview changes with --dry-run before using --execute.

# Preview resetting all input topics to a specific timestamp
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --group my-streams-app \
  --reset-offsets --all-input-topics --to-datetime 2025-01-31T23:57:00.000 \
  --dry-run

# Apply the reset
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --group my-streams-app \
  --reset-offsets --all-input-topics --to-datetime 2025-01-31T23:57:00.000 \
  --execute

Delete offsets to force re-consumption

Delete offsets for all or specific input topics to have the group re-read data on restart.

# Delete offsets for all input topics (execute)
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --group my-streams-app \
  --delete-offsets --all-input-topics --execute

# Delete offsets for specific topics
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --group my-streams-app \
  --delete-offsets --topic input-a --topic input-b --execute

Delete a Streams group (cleanup)

Delete broker-side Streams metadata for a group and optionally remove a subset of internal topics.

# Delete Streams group metadata
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --delete --group my-streams-app

# Delete a subset of internal topics alongside the group (use with care)
kafka-streams-groups.sh --bootstrap-server localhost:9092 \
  --delete --group my-streams-app \
  --internal-topics my-app-repartition-0,my-app-changelog

All options and flags

Core actions

  • --list: List Streams groups. Use --state to display/filter by state.
  • --describe: Describe a group selected by --group. Combine with:
    • --state (group state and epochs), --members (members and assignments), --offsets (input and repartition topics offsets/lag).
    • --verbose for additional details (e.g., leader epochs where applicable).
  • --reset-offsets: Reset input-topic offsets (one group at a time; instances should be inactive). Choose exactly one specifier:
    • --to-earliest, --to-latest, --to-current, --to-offset <n>
    • --by-duration <PnDTnHnMnS>, --to-datetime <YYYY-MM-DDTHH:mm:SS.sss>
    • --shift-by <n> (±), --from-file (CSV) Scope:
    • --all-input-topics or one/more --topic <name>; some builds also support --all-topics (all input topics per broker topology metadata). Safety:
    • Requires --dry-run or --execute.
  • --delete-offsets: Delete offsets for --all-input-topics, specific --topic names, or --from-file.
  • --delete: Delete Streams group metadata; optionally pass --internal-topics <list> to delete a subset of internal topics.

Common flags

  • --group <id>: Target Streams group (application.id).
  • --all-groups: Operate on all groups (allowed with --delete).
  • --bootstrap-server <host:port>: Broker(s) to connect to (required).
  • --command-config <file>: Properties for AdminClient (security, timeouts, etc.).
  • --timeout <ms>: Wait time for group stabilization in some operations (default: 5000ms).
  • --dry-run, --execute: Preview vs apply for mutating operations.
  • --help, --version, --verbose: Usage, version, verbosity.

Best practices and safety

  • Preview changes with --dry-run to verify topic scope and impact before --execute.
  • Use --internal-topics carefully: deleting internal topics removes state backing topics; only do this when you intend to rebuild state from input topics.

This page documents kafka-streams-groups.sh capabilities for Streams groups as defined by KIP‑1071 and implemented in Apache Kafka.

Last modified February 25, 2026: Update 4.2 Kafka Streams documentation (#818) (94f3446554)