Switching From 5-Node Cluster Mode To 3-Node Cluster Mode; Replacing A Master Mdm - Dell EMC VxFlex Ready Node User Manual

Managing System Objects

Switching from 5-node cluster mode to 3-node cluster mode

Replacing a Master MDM

Dell EMC VxFlex Ready Node AMS User Guide
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The Switch to 5 Node Cluster Mode window is displayed.
2. Select one Standby MDM and one Standby Tie Breaker.
3. Click OK.
Results
The selected standbys are added to the cluster, and the cluster is now operating in 5-
node mode.
Decrease the number of nodes in an MDM cluster from five to three nodes, using the
VxFlex OS GUI.
About this task
When possible, it is preferable to work in 5-node mode, especially in large systems.
However, if it is necessary to reduce the number of nodes participating in the MDM
cluster, follow these procedures to ensure a graceful change of cluster size.
Procedure
1. In the Hardware view, click the Cluster menu, and select Decrease to 3 Node
Cluster Mode.
The Switch to 3 Node Cluster Mode window is displayed.
2. Select one MDM and one Tie Breaker for removal from the cluster.
3. Click OK.
Results
The cluster switches to 3-node cluster mode. The nodes that you removed from the
MDM cluster revert to standbys.
Replace a Master MDM with a Slave MDM, using the VxFlex OS GUI.
About this task
If you need to remove a server from a system, and that server is currently hosting the
Master MDM, switch cluster control from the Master MDM to one of the Slave MDMs
in the cluster. This operation ensures a graceful transfer of control, before removal of
the server.
Procedure
1. In the Hardware view, click the Cluster menu, and select Replace Master
MDM.