FAQ

Riak MDC Replication FAQ

Can fullsync replication run between clusters having rings of different sizes?

• No

Can realtime replication run between clusters having different n values?

• Yes, but very inefficiently

How can it be determined if backpressure is being applied during replication?

• look at netstat -a output and see if Recv-Q and Send-Q and growing

How can network performance between source + sink be measured

• iperf

Do replicated puts show up in riak-admin status stats?

• yes, here are the rt puts for a single object on a sink with an n_val=3:

vnode_puts : 3
vnode_puts_total : 3

• see also: https://github.com/basho/riak_repl/blob/develop/src/riak_repl_util.erl#L109

Do bucket hooks on the sink fire?

• No, puts on the sink use disable_hooks: https://github.com/basho/riak_repl/blob/develop/src/riak_repl_util.erl#L117

What happens when the same keys are written into both source and sink?

• be extra darn careful about resolving siblings on either side!
• kittens die

How does repl work on EC2?

• meh
• customers should be comfortable and educated with EC2 BEFORE using Riak EE on it
• customers should probably look at this doc first: http://docs.basho.com/riak/latest/ops/tuning/aws/