ES on master or slave?

[kontrabass]

Given a master DB server (Xeon E3, SSD's in RAID 1, 16GB RAM) and a slave DB server (Xeon E3, 7200RPM sata drive, 8GB RAM), where should elasticsearch be installed and run? Database has 14M posts, 19GB in size.

Thanks!

 

[digitalpoint]

If you want to take advantage of Elastic Search's sharding for load balancing and redundancy (one server goes down and everything is still searchable), you would want to install it on both.