Setting Up Cross-Mirroring Between Unsecure Clusters
Describes how to edit the mapr-clusters.conf
file to mirror volumes
between unsecure clusters.
About this task
mapr-clusters.conf
file on the cluster of the source volume and
create an entry for each additional cluster that hosts a mirror of the volume. The entry
must list the name of the cluster, followed by a space-separated list of hostnames and
ports for the CLDB nodes of the cluster. In addition, use the secure
parameter to specify whether the clusters are secure or non-secure. See Configuring Secure Clusters for Cross-Cluster Mirroring and Replication for more information about
generating tickets for secure clusters. NOTE When mirroring between clusters, servers in
one cluster cannot use the same IP addresses as servers in the other cluster. For
example, if node A in cluster A has a private IP address 10.10.20.29, no server in
cluster B can have the same private IP address. Also, all the servers in one cluster
must be able to reach all the servers in the other cluster and vice versa. For example,
suppose 10.10.20.29 is the only IP address used by node A in cluster A; then all servers
in cluster B should be able to reach the IP address 10.10.20.29.
To set up
cross-mirroring between unsecure clusters:Procedure
- Review the requirements for Creating Remote Mirrors before you begin.
-
On each cluster, make a note of the cluster name and CLDB nodes (the first line in
mapr-clusters.conf
) -
On each webserver and CLDB node, add the CLDB nodes of the remote cluster to
/opt/mapr/conf/mapr-clusters.conf
, using the following format:clustername1 <CLDB> <CLDB> <CLDB> [ clustername2 <CLDB> <CLDB> <CLDB> ] [ ... ]
For example, suppose you have a cluster,
clusterA,
with two CLDB nodes,nodeA
andnodeB
. Now you want to add a second cluster calledclusterB
with CLDB nodesnodeC
andnodeD
. Edit themapr-clusters.conf
file and add the line forclusterB
as shown:clusterA nodeA:7222 nodeB:7222 clusterB nodeC:7222 nodeD:7222
WARNING You must include the port number in the CLDB hostname notation.Here:- First line contains cluster name and CLDB nodes of cluster A (the local cluster)
- Second line contains cluster name and CLDB nodes of cluster B (the remote cluster)
mapr-clusters.conf
file for cluster B with 2 CLDB nodes (nodeC
andnodeD
) looks as follows:clusterB nodeC:7222 nodeD:7222 clusterA nodeA:7222 nodeB:7222
By creating additional entries in the
mapr-clusters.conf
file, you can mirror from one cluster to several others. -
Set
secure=false
if both clusters are not secure. If both the clusters are secure, see Configuring Secure Clusters for Cross-Cluster Mirroring and Replication for more information.WARNING Mirroring only works between two secure clusters or between two non-secure clusters. Mirroring does not work when one cluster is secure and the other is non-secure. -
On each cluster, restart the
mapr-apiserver
service on all nodes where it is running.