Hello again :) On 4/10/06, Shawn Green <[EMAIL PROTECTED]> wrote: > > First rule: Do NOT share data files between server processes. Nothing > should directly interact with a datafile other than the server to which > it belongs. This includes other server processes as well as direct user > actions or actions from a third-party program. > > There are structures and procedures that each MySQL process maintains > that assumes that each process has exclusive control over every data > file it is managing. Sharing files between two processes is highly > discouraged. >
something still bothers me very much .. here i quoted the manual .. ( http://dev.mysql.com/doc/refman/5.0/en/multiple-servers.html) ===================================================== With very limited exceptions, each server should use a different data directory, which is specified using the --datadir=*path* option. *Warning*: Normally, you should never have two servers that update data in the same databases. This may lead to unpleasant surprises if your operating system does not support fault-free system locking. If (despite this warning) you run multiple servers using the same data directory and they have logging enabled, you must use the appropriate options to specify log filenames that are unique to each server. Otherwise, the servers try to log to the same files. Please note that this kind of setup only works with MyISAM and MERGEtables, and not with any of the other storage engines. ===================================================== so, mysql it self never mention that it could not be done .. beside, there shouldn't be any issue with concurency .. one always write, the other always read .. unless, mysql lock the tables to read it, and never let it go???? anyway .. while i am preparing to try FEDERATED .. can you guys please tell me why is it impossible to be done? and here is another quote ( http://dev.mysql.com/books/hpmysql-excerpts/ch07.html) : ===================================================== To get around that limitation, you can run two copies of MySQL on the slave machine. Each MySQL instance is responsible for replicating a different master. In fact, there's no reason you couldn't do this for 5 or 10 distinct MySQL masters. As long as the slave has sufficient disk space, I/O, and CPU power to keep up with all the masters, you shouldn't have any problems. ===================================================== jeremy even told something about writing to the same table from two master :D really .. i need someone's sucessful experience in multi mastering :) thanks - Leo
