Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Wed, Aug 22, 2007 at 04:48:07PM +0200, Pierguido wrote: > Hi all. > I'm trying to set up a little cluster with drbd and mysql. > Reading on the mysql site, i found "MySQL does not support Active/Active > configurations using DRBD “out of the box”". > Does that mean that mysql has some problem with a primary/primary drbd > setup? step back a little. one single computer. one mysql instance. one data directory. great. can you add a second mysql instance, on the same box, using the same data directory? no. so replicating it using drbd and a cluster file system, and then simultaneously accessing it with a second mysql instance on a second box can not magically make it work. to have more than one application instance access the same data source, they have to coordinate access, whether they run on a single host, or on two different hosts. not only writes (that should be obvious), but also reads, to avoid cache coherency issues. if the application does not provide such a coordination layer, it won't work. this is not limited to mysql. your application has to be "cluster aware" to do this. -- : Lars Ellenberg Tel +43-1-8178292-0 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Vivenotgasse 48, A-1120 Vienna/Europe http://www.linbit.com : __ please use the "List-Reply" function of your email client.