The version and patch level of the backup and the target managed unit must match exactly. So 11.0 collector backup to 11.3 managed unit is not recommended.
When the backup is restored, the restored managed unit should be the same. So it will want to connect to the central manager of the backed up unit.
There is no requirement that the hardware be the same. Just the Software and patch levels, and the managed unit type (collector, aggregator, CM). However, hardware of the new managed unit should match or exceed capabilities of old hardware, and must meet minimum requirements for that type of system, as described in system requirement section of Knowledge center.
Hope this helps!
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Louis Fuka
IBM
Austin TX
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