mysql - Scaling and High Availability of Oracle Database -


as per oracle docs can use oracle rac ha , scaling database.

i see oracle rac uses shared persistence ( san based) share data ( data files, control files of db) among multiple instances http://docs.oracle.com/database/121/haovw/architectures.htm#chdbijaj.

but, @ webscale( facebook kind of scale) san bottleneck ( central point), right ? also, special hardware instead of commodity hardware , single point of failure.

so, questions ,

1. require oracle rac ha , scale, can not setup scaling , ha without rac using standard oracle instances master , slave configurations ?

2. how can make oracle database instances ( each it's own disk db data) work of following

  • multi-master , slave configuration synchronous 2 phase commit
  • "master , slave configuration" slave taking on master, in case master fails.
  • the way mysql "multi-master" or "master , slave configurations".

ps: couldn't find answers on web, think answers others too.

if want implement 'master/slave' configuration, you're looking @ oracle dataguard must run on enterprise edition , cost ad-on.

dataguard copy redo log data on server (in real-time) , update data files on 'slave' server. dataguard can configured standby server open read-only queries.

it can handle items bullet out in 2nd point.


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