List:Cluster« Previous MessageNext Message »
From:Peter Romfeld Date:October 10 2013 8:12am
Subject:dual-channel replication
View as plain text  
Hi,

I setup 3 ndbclusters with circular replication between the clusters,
everything working fine so far. Now I am at the chapter about
2-channel-replication
https://dev.mysql.com/doc/refman/5.6/en/mysql-cluster-replication-failover.html

right now i have in each region 2x mysqld-nodes, 2x mgmt-nodes, 2x
data-nodes.
I setup circular replication between Region-1-mysqld-node-1
Region-2-mysqld-node1 Region-3-mysqld-node1, from my understanding this
replication cycle is one Channel,
now i did the same thing on Region1-mysqld-node-2 Region-2-mysqld-node2
Region-3-mysqld-node2 with the only difference that i used
"skip-slave-start".
If now lets say Region-1-mysqld-node-1 gets unreachable and breaks the
replication, how do i switch to the second replication-cycle? I am not sure
from where to get
SELECT @latest:=MAX(epoch) FROM mysql.ndb_apply_status;
SELECT @file:=SUBSTRING_INDEX(next_file, '/', -1), @pos:=next_position FROM
mysql.ndb_binlog_index WHERE epoch = @latest ORDER BY epoch ASC LIMIT 1;

can someone help me on which servers i should execute the commands provided
in the guide?

Thanks very much!
Peter

Thread
dual-channel replicationPeter Romfeld10 Oct