Hi Dieter!
The answer is quite simple: do not use multimaster replication in a production environment. In most cases the requirement for multimaster replication is just based on poor directory design.
If this is a "do not use feature", for what reason has it been included in the software, in the first place.
Slapd in a synchronized environment is, with a few exceptions which have only been fixed recently, rock stable, I know of environments with up to 150 consumers.
When you say "synchronized", do you mean one master and n slaves?
When you say, the requirement for N-way multi-master is usually poor directory design, I wonder if I am suffering from a misconception here, i.e. mixing up N-way multi-master and mirror mode possibly.
What we want to achieve is a HA solution where *all* directory data is stored on more than one physical machine. I know I can do that by having a master and a slave. But then I would need to have a mechanism entirely external to slapd that if the master fails I turn the slave into a master and vice versa. (However this could be reliably achieved.)
So the idea for N-way multi-master was just: I can point the DNS entry to whatever server in my cluster (possibly there may be more than two) and it will be a writeable directory and I won't ever loose any information I write into that LDAP cloud.
Regards, Torsten
Dieter Kluenter schrieb:
"Torsten Schlabach (Tascel eG)" tschlabach@tascel.net writes:
Hi Quanah!
I suggest you go read the CHANGES log for what has been fixed between 2.4.11 and the latest stable 2.4.19.
I need to say, it worries me a bit that for problems with a core feature which has been around for quite some time, the answer is more often that I like to hear: You need to use the latest version released last week / month or so.
I have indeed read the CHANGES and seen that some issues have been fixed. I have no idea if we are affected by those issues or now.
Also how would I know that *now* in 2.4.19 all problems are fixed and the answer next week won't be: You need to use 2.4.20.
But as this is a FOSS project and not a product we pay for, we understand that we should not blame people but try and help if we find a a problem.
For that reason I have asked in my email for help on *understanding* and *diagnosing* problems to have a chance to contribute in case we will find any new issues.
Also our customers may not like it if in case of a problem we tell them: Let's wait if in some weeks a new release will come which will fix it or not. So I'd rather be in a position to get my hands dirty myself in case of problems.
The answer is quite simple: do not use multimaster replication in a production environment. In most cases the requirement for multimaster replication is just based on poor directory design. Slapd as a stand alone directory is rock stable and outperforms all other products I know of. Slapd in a synchronized environment is, with a few exceptions which have only been fixed recently, rock stable, I know of environments with up to 150 consumers.
-Dieter