Memcached vs Redis

Here are few differences mentioned on one of  Udemy Practice Test:

Redis stores data persistently but not memcached. 
Redis supports multi-AZ with read replicas in another AZ in same region.
  • You can have a fully automated, fault tolerant ElastiCache-Redis implementation by enabling both cluster mode and multi-AZ failover
  • Memcached engine does not support Multi-AZ failover or replication.
References:

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