Managing fault tolerance
To increase fault tolerance, rdsync
, a host status management agent, is integrated into the Managed Service for Redis architecture. Host status is stored in the distributed configuration management system. If the connection to the DCS (distributed configuration store, e.g., ZooKeeper, etcd, or Consul) is lost, the agent switches the host to protected mode
Thanks to the rdsync
agent running in a Redis cluster:
-
Configurations that consist of an even number of hosts are fault-tolerant.
-
Handling client requests
for the name of a host available for writes is consistent with therdsync
agent and provides up-to-date information to clients, since the statuses of all hosts are known. -
You do not lose data when using the
WAIT
command withN/2
available replicas, whereN
is the number of cluster hosts.