IBM N Series Hardware Manual page 113

Tip: Under normal conditions, you do not need to perform takeover/giveback on an IBM N
series system. Usually you need to use it only if a controller needs to be halted or rebooted
for maintenance.
1. As illustrated in Figure 7-6, you can perform the takeover by using System Manager and
clicking Active/Active Configuration  Takeover.
Figure 7-6 System Manager initiating takeover
Chapter 7. Highly Available controller pairs
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