mirror of https://github.com/schoebel/mars
69 lines
2.6 KiB
Plaintext
69 lines
2.6 KiB
Plaintext
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GPLed software AS IS, sponsored by 1&1 Internet AG (www.1und1.de).
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MARS Light is almost a drop-in replacement for DRBD
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(that is, block-level storage replication).
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In contrast to plain DRBD, it works _asynchronously_ and over
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arbitrary distances.
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WARNING! Current stage is BETA. Don't put productive data on it!
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Documentation: currently very rudimentary, some even in German.
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This will be fixed soon.
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Concepts:
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There is a 2-years old concept paper in German which is so much outdated,
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that I don't want to publish it. Please be patient until I write a
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comprehensive paper at the concept level in English.
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For the meantime, please look at my presentation about MARS at LCA2013
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(linux.conf.au).
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History:
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As you can see in the git log, it evolved from a very experimental
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concept study, starting in the Summer of 2010.
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At this time, I was working on it in my spare time.
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In Summer 2011, an "official" internal 1&1 project started, which aimed
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to deliver a proof of concept.
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In February 2012, a pilot system was rolled out to an internal statistics
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server, which collects statistics data from thousands of other servers,
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and thus produces a very heavy random-access write load, formerly
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replicated with DRBD (which led to performance problems due to massive
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randomness). After switching to MARS, the performance was provably
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better.
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This server was selected because potential loss of statistics data
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would be not be that critical as with other productive data, but
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nevertheless it operates on productive data and loads.
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After curing some small infancy problems, this server runs until today
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(end of January 2013) without problems. Our sysadmins even switched the
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primary side a few times, without informing me, so I could
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sleep better at night without knowing what they did ;)
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In Summer 2012, the next "official" internal 1&1 project started. Its goal
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is to reach enterprise grade, and therefore to rollout MARS Light on
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~10 productive servers, starting with less critical systems like ones
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for test webspaces etc. This project will continue until Summer 2013.
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Hopefully, there will be a followup project for mass rollout to some
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thousands of servers.
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In December 2012 (shortly before Christmas), I got the official permission
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from our CTO Henning Kettler to publish MARS under GPL on github.
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Many thanks to him!
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Before that point, I was bound to my working contract which keeps internal
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software as secret by default (when there is no explicit permission).
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Now there is a chance to build up an opensource
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community for MARS, partially outside of 1&1.
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Please contribute! I will be open.
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I also try to respect the guidelines from Linus, but probably this
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will need more work. Help is always welcome!
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