Dell PowerVault 775N (Rackmount NAS Appliance) - Manual (Page 18)

12. Repeat this procedure for cluster node 2.
Installing and Configuring the Shared Storage System
Clustering PowerVault Storage Systems
If you are upgrading an existing PowerVault 21xS or 22xS storage system to meet the cluster requirements for the shared
storage system, you may need to install additional hard drives and/or one of the following management modules in the
shared storage system:
SCSI SEMM (PowerVault 21xS only)
EMM (PowerVault 22xS only)
The size and number of drives you add depends on the RAID level you want to use, the number of hard drives installed in
your system, and the number of application programs you want to run in your cluster environment.
See the Dell PowerVault 200S, 201S, 210S, and 211S Storage Systems Installation and Service Guide or the Dell PowerVault
220S and 221S System Installation and Troubleshooting Guide for information about installing the hard drives in the
PowerVault 22xS storage system.
NOTE: In cluster mode, the last slot (SCSI ID 15) in the PowerVault 22xS is not used; SCSI ID 15 is used for the
primary EMM.
Configuring the PowerVault 21xS Storage System for Cluster Mode
To ensure that both NAS systems recognize all the drives in the storage system, you must enable forced-joined mode on the
SEMMs installed in each storage system that you will share between the two storage systems for clustering. This mode
prevents the storage system from operating in a dual-bus split backplane configuration (2 x 4 or 2 x 6) when two cables are
attached.
The SEMMs are identified by a label adjacent to the SCSI connector. Two identical SEMMs installed in each storage system are
required for cluster operation. You cannot use one SEMM.
See the Dell PowerVault 200S, 201S, 210S, and 211S Storage Systems Installation and Service Guide for more information
on installing and configuring the SEMMs.
To configure the SEMMs for forced join mode:
1. Locate the two-pin jumper labeled "FORCED JOINED JP8" on the SEMM, as shown in Figure 2-1 .
The SEMM is shipped with a jumper plug that is connected to only one jumper pin.
Figure 2-1. SEMM Configuration