RBD-REPLAY(8)

📦
version 20.2.4 · 20 versions
, in ubuntu stonking

🌸 RBD-REPLAY 🌸

okay bestie, welcome to rbd-replay, aka the rados block device (RBD) workload replay machine 💅 this page lives in section 8 of the manual (the sysadmin-y one, iykyk) and it's gonna be your new obsession.

✨ SYNOPSIS ✨

rbd-replay [ options ] replay_file

🦋 DESCRIPTION 🦋

rbd-replay is a utility for replaying rados block device (RBD) workloads. that's it, that's the whole vibe — it takes a recorded workload and plays it back. iconic behavior honestly 🎀

💖 OPTIONS 💖

  • -c ceph.conf, --conf ceph.conf — use ceph.conf as the configuration file instead of the default /etc/ceph/ceph.conf, so it can figure out the monitor addresses during startup. like bringing your own map instead of using the one at the front desk 🗺️
  • -p pool, --pool pool — hang out with the given pool. defaults to 'rbd', no cap.
  • --latency-multiplier — multiplies the inter-request latencies. default: 1. so it's literally the speed dial for your replay ⏱️🔥
  • --read-only — only replays the non-destructive requests. safety queen behavior, we love 🫶
  • --map-image rule — adds a rule that maps image names in the trace to image names in the replay cluster. a rule like image1@snap1=image2@snap2 would map snap1 of image1 to snap2 of image2. lowkey a glow-up for your image names ✨
  • --dump-perf-counters — experimental!! dumps performance counters to standard out before an image is closed. heads up bestie: the counters may get dumped multiple times if multiple images are closed, or if the same image is opened and closed multiple times. and the counters and what they even mean may change between versions. so like, don't build your whole personality on them 🙈
⚠️ for real though — --dump-perf-counters is marked experimental, and performance counters plus their meaning may change between versions.

🌈 EXAMPLES 🌈

wanna replay workload1 as fast as humanly possible? periodt:

rbd-replay --latency-multiplier=0 workload1

wanna replay workload1 but swap in test_image instead of prod_image? yes queen, protect prod:

rbd-replay --map-image=prod_image=test_image workload1

👑 AVAILABILITY 👑

rbd-replay is part of Ceph, a massively scalable, open-source, distributed storage system. please refer to the Ceph documentation at <https://docs.ceph.com> for more information. go read the docs, they're the main character 💜

💀 SEE ALSO 💀

rbd-replay-prep <>(8), rbd <>(8)

2010-2014, Inktank Storage, Inc. and contributors. Licensed under Creative Commons Attribution Share Alike 3.0 (CC-BY-SA-3.0)

and that's the whole page, bestie 💖 this was the dev version, dated Oct 06, 2026 — go slay some replays, you've got this 🦋✨🌸

📦 where this page comes from