The Corosync Cluster Engine is an open source implementation of the Totem Single Ring Ordering and Membership protocol. It was originally derived from the OpenAIS project and licensed under the new BSD License. The mission of the Corosync effort is to develop, release, and support a community-defined, open source cluster.
A simple availability manager that restarts the application process when it has failed.
A configuration and statistics in-memory database that provides the ability to set, retrieve, and receive change notifications of information.
A quorum system that notifies applications when quorum is achieved or lost.
The software is designed to operate on UDP/IP and InfiniBand networks.
Architecture
The software is composed of an executive binary which uses a client-server communication model between libraries and service engines. Loadable modules, called service engines, are loaded into the Corosync Cluster Engine and use the services provided by the Corosync Service Engine internal API.
The services provided by the Corosync Service Engine internal API are:
An implementation of the Totem Single Ring Ordering and Membership[2] protocol providing the Extended Virtual Synchrony model[3] for messaging and membership.
Systems to route IPC and Totem messages to the correct service engines.
Additionally Corosync provides several default service engines that are used via C APIs:
cpg - Closed Process Group
sam - Simple Availability Manager
confdb - Configuration and Statistics database
quorum - Provides notifications of gain or loss of quorum
History
The project was formally announced in July 2008 via a conference paper at the Ottawa Linux Symposium.[5] The source code of OpenAIS was refactored such that the core infrastructure components were placed into Corosync and the SA Forum APIs were kept in OpenAIS.
In the second version of corosync, published in 2012, quorum subsystem was changed and integrated into the daemon.[6] This version is available since Fedora 17 and RHEL7.[7]
Flatiron branch (1.4.x) development ended with 1.4.10 release.[8] Needle branch was announced stable with 2.0.0 release on 10 April 2012.[9][10] Development of this branch stopped with 2.4.6 release on 9 November 2022, because 3.x branch (Camelback) was considered to be stable after almost 4 years of work.[9]
Corosync High Performance Shared Memory IPC Reusable C Library
February 06, 2023
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The Corosync Cluster Engine is an open source implementation of the Totem Single Ring Ordering and Membership protocol It was originally derived from the OpenAIS project and licensed under the new BSD License The mission of the Corosync effort is to develop release and support a community defined open source cluster Corosync Cluster EngineDeveloper s The Corosync Development CommunityInitial release2008 15 years ago 2008 Stable release3 1 7 1 Camelback 15 November 2022Repositorygithub wbr com wbr corosync wbr corosyncWritten inCOperating systemCross platformTypeGroup Communication SystemLicenseNew BSD LicenseWebsitecorosync wbr github wbr io wbr corosync wbr Contents 1 Features 2 Architecture 3 History 4 See also 5 References 6 External linksFeatures EditThe Corosync Cluster Engine is a group communication system with additional features for implementing high availability within applications The project provides four C API features A closed process group communication model with virtual synchrony guarantees for creating replicated state machines A simple availability manager that restarts the application process when it has failed A configuration and statistics in memory database that provides the ability to set retrieve and receive change notifications of information A quorum system that notifies applications when quorum is achieved or lost The software is designed to operate on UDP IP and InfiniBand networks Architecture EditThe software is composed of an executive binary which uses a client server communication model between libraries and service engines Loadable modules called service engines are loaded into the Corosync Cluster Engine and use the services provided by the Corosync Service Engine internal API The services provided by the Corosync Service Engine internal API are An implementation of the Totem Single Ring Ordering and Membership 2 protocol providing the Extended Virtual Synchrony model 3 for messaging and membership The coroipc high performance shared memory IPC system 4 An object database that implements the in memory database model Systems to route IPC and Totem messages to the correct service engines Additionally Corosync provides several default service engines that are used via C APIs cpg Closed Process Group sam Simple Availability Manager confdb Configuration and Statistics database quorum Provides notifications of gain or loss of quorumHistory EditThe project was formally announced in July 2008 via a conference paper at the Ottawa Linux Symposium 5 The source code of OpenAIS was refactored such that the core infrastructure components were placed into Corosync and the SA Forum APIs were kept in OpenAIS In the second version of corosync published in 2012 quorum subsystem was changed and integrated into the daemon 6 This version is available since Fedora 17 and RHEL7 7 Flatiron branch 1 4 x development ended with 1 4 10 release 8 Needle branch was announced stable with 2 0 0 release on 10 April 2012 9 10 Development of this branch stopped with 2 4 6 release on 9 November 2022 because 3 x branch Camelback was considered to be stable after almost 4 years of work 9 See also EditLinux HA Pacemaker software References Edit https github com corosync corosync releases tag v3 1 7 retrieved 23 November 2022 Amir Y Moser L E Melliar Smith P M Agarwal D A Ciarfella P November 1995 The Totem Single Ring Ordering and Membership Protocol ACM Transactions on Computer Systems 13 4 311 342 doi 10 1145 210223 210224 S2CID 15165593 Moser L E Amir Y Melliar Smith P M Agarwal D A November 1995 Extended Virtual Synchrony ACM Transactions on Computer Systems 13 4 311 342 doi 10 1145 210223 210224 S2CID 15165593 Also in Proceedings of DCS pp 56 65 1994 Dake S July 2009 The Corosync High Performance Shared Memory IPC Reusable C Library PDF Proceedings of the Linux Symposium 61 68 Dake S Caulfield C Beekhof A July 2008 The Corosync Cluster Engine PDF Proceedings of the Linux Symposium 85 99 Christine Caulfield New quorum features in Corosync 2 2012 2016 in English Linux Cluster next generation LVEE 2013 Releases v1 4 10 Retrieved 23 November 2022 a b Releases v2 4 6 Retrieved 23 November 2022 Releases v2 0 0 Retrieved 23 November 2022 External links EditOfficial website The Totem Single Ring Ordering and Membership Protocol CiteSeerX 10 1 1 37 767 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Totem A Reliable Ordered Delivery Protocol for Interconnected Local Area Networks CiteSeerX 10 1 1 52 4028 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Extended Virtual Synchrony model CiteSeerX 10 1 1 55 8677 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Corosync High Performance Shared Memory IPC Reusable C Library Retrieved from https en wikipedia org w index php title Corosync Cluster Engine amp oldid 1124273979, wikipedia, wiki, book, books, library,
