Hi Gerrard, Since you are already mentioning OSPF, how about grouping the Masterservers into "zones" and have only one of the hosts taking care of the communication to other "zones". Changes could always only be replicated via the "communication master". The main problem that arises here is the potential outage of one of those "communication masters", this could be solved by either an election process or by an explicit order. I think this would be a good way to go because it is very close to real life scenarios form my point of view, I most likely have a view masters in geographically distributed locations, but not tens of servers in one location ( maybe already counting e.g. different buildings on a campus as locations ) Not sure if that is a way to go, but maybe it helps a little Best Regards, Soeren Malchow CIO Phone: +49 40 806008 120 Mobile: +49 171 5525102 Email: soeren.malchow@xxxxxxxx Web: www.mcon.net MCon Germany GmbH Neuer Pferdemarkt 1 20359 Hamburg Germany Berlin . Hamburg . Karlsruhe . Koeln . Muenchen Traderegister HRB 110600 Local Court Mannheim | VAT-Id. No.: DE235236333 | Tax No.: 35 007 055033 Managing Partner: Dirk Meissner, Guenther Kreuzpaintner, Soeren Malchow Member of MCon Group Austria . China . Czech Republic . France . Germany . Japan . Malaysia . Russia . South Korea . Switzerland . UK . USA This e-mail may contain confidential and/ or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material contained in this e-mail is strictly prohibited. Please consider the environment before printing this e-mail -----Original Message----- From: 389-devel-bounces@xxxxxxxxxxxxxxxxxxxxxxx [mailto:389-devel-bounces@xxxxxxxxxxxxxxxxxxxxxxx] On Behalf Of Gerrard Geldenhuis Sent: Friday, December 03, 2010 5:25 PM To: '389-devel@xxxxxxxxxxxxxxxxxxxxxxx' Subject: [389-devel] Thought excersize: A different take on replication Hi We were discussing different setups of replication agreements (multi master) between a large number of hosts and ways to minimize contention during updates with interconnected hosts. For example the same change might arrive on a host from two other hosts via different paths at the same time causing "errors" in the log because of exponential back off. If you have to many connections you get a replication storm, to little connections and replication takes to long. The problem to us sounds very much like a network problem or maybe the effectiveness of the underlying database to lock the data more effectively. We dreamt up a couple of solutions/ideas and I am writing this email to illicit some more discussions and/or comments. One solution would be to change the underlying database to one that supports improved granular locking (firebird comes to mind ) . Another idea we discussed was based on the following question: What if you could only define the list of master servers and let the master servers figure out the details with regards to doing multi mastering and distributing the data and taking care of broken paths? There is similarities with OSPF... Do you have any thoughts on this? Have you had similar ideas? Are we missing the point? Regards ________________________________________________________________________ In order to protect our email recipients, Betfair Group use SkyScan from MessageLabs to scan all Incoming and Outgoing mail for viruses. ________________________________________________________________________ -- 389-devel mailing list 389-devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/389-devel -- 389-devel mailing list 389-devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/389-devel
