Nera WILINK I System Manual page 128

Shadow: Normally the Shadow version is the backup version. Each time a
new SW File is downloaded to the SU, it will be stored as a Shadow version,
replacing the previous Shadow Version.
The process of upgrading to a new SW version is controlled by the NPU, and is
performed using one of the SU SW files installed in the NPU. If the specified SU
SW file does not exist in the SU, it will be downloaded to the SU and the
requested operation will be executed, as described below. If it already exists in
the SU, then actual loading is not necessary.
The following options are available in the SW Version Control menu:
Show SW Versions
None
Download
Run from Shadow
Set as Main
4.9.6.2.4.1 Show SW Versions
Select this option to view the following information:
SW Versions in SU:
Available Versions in NPU: The available SU SW file names and the SW
Version of each file.
4.9.6.2.4.2 None
Select None to cancel a pending request for another operation (an operations will
be executed only after the next reset).
WILINK I MODULAR BASE STATION SYSTEM MANUAL
Main SW File Name
Main SW Version
Shadow SW File Name
Shadow SW Version
Running From: Main or Shadow
SU Menu
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