Memcached is a cache, not storage, you really shouldn't use it as such. When you set a value in memcached, you have no guarantees whatsoever that you'll be able to get the value back afterwards. You're guaranteed to get the latest value set if you get something, and you're guaranteed to not get a value if it's been deleted or has expired. But there are a lot of factors that can cause a value to be spontaneously evicted, to say nothing of the fact that you lose everything if you restart it or if the machine crashes.
Also note that any replication functionality can lead to inconsistency, since there are no built-in mechanisms for resolving that, you can just hope that your failover server has the same data as the original one. If you want storage, then get a piece of software that actually offers storage, there are plenty to choose from. But memcached is probably the wrong choice for you. If you only need key-value storage, then I suggest you check out Cassandra, it scales pretty linearly in that scenario. Or you could check out hstore in Postgresql, but you probably need to make your own sharding for that. /Henrik On Mon, Mar 11, 2013 at 9:57 AM, Oleksandr Drach <luckyred...@gmail.com>wrote: > Hello Dormando! > Thanks for your reply. > > Description and requirements are: > - Memcached will be used a primary storage (i.e. not for caching MySQL). > - It should have failover feature (in case if one server fails all > connections goes to another server). > > Basically something like Master-Slave will be sufficient, but > Master-Master architecture is more acceptable. > Thanks! > > > On Sunday, March 10, 2013 1:58:16 AM UTC+2, Dormando wrote: > >> > Dear memcached community, >> > It would be really good to build a failover memcached cluster.� >> > As I know this functionality is not provided by default.� >> > Hence as options - you may use CouchBase Server or something like >> Repcached. >> > Both of them has disadvantages: CouchBase Server is much slower, >> �Repcached works with legacy memcached version 1.2.8 >> > >> > Based on your�experience�what is the best way to build cluster of >> memcached servers? >> > >> > Thanks in advance! >> >> Hi, >> >> This depends on why you need that second cluster and what the constraints >> are for it. >> >> You can do client side replication via libmemcached which will handle a >> lot of potential use cases. Though oftentimes people who are attempting >> to >> do this are doing so because they don't understand normal memcached >> clustering very well. >> >> So it'd be useful to state all of your requirements up front. Then we can >> make a real recommendation/etc. >> > -- > > --- > You received this message because you are subscribed to the Google Groups > "memcached" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to memcached+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
