Enable Read And Write Cache; Sample Error Message; Remedy; Using Unisphere - EMC VNX VG2 Setup Manual

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Backend Storage Requirements Check Failed Error

Enable read and write cache

!
Sample error
message

Remedy

Using Unisphere

194 EMC VNX VG2/VG8 Gateway Configuration Setup Guide
CAUTION
Do not change the read and write cache settings of an existing array without the
customer's permission. If the VNX is connected to other hosts, disabling the array
read and write cache will impact the other hosts connected to the VNX.
If the INSTRUCTIONS line of the error message indicates that you should enable the
write cache, the VNX array does not have the write cache enabled. You must enable
the write cache on the array before you can complete your installation or upgrade.
Backend Storage Requirements Check Failed:
REQUIREMENT: Is_Write_Cache_Enabled = True
ID: 000185400111 FOUND: False INSTRUCTIONS: Enable write cache.
The optimal write cache setting depends on all of the hosts/applications that are
using the VNX array and is beyond the scope of this setup guide. The engineering
white paper EMC CLARiiON Best Practices for Fibre Channel Storage explains how to
calculate the read and write cache settings. This document is available from the
Powerlink website at:
http://Powerlink.EMC.com
To verify the VNX array write cache setting by using Unisphere:
1. Right-click the array name on the main Unisphere page and select Properties.
2. On the SP Cache tab, ensure the Read and Write Cache checkboxes are selected.
3. Click the SP Memory tab. The dialog box shown in
appears.
Figure 107 on page 195