I have the same question please @Arun_Paul, and also... I noticed that the MG41/41E, 51/51E and 52/52E Technical Specifications docs at https://documentation.meraki.com/MG/MG_Datasheets all contain the following statement, but the MG21/21E doc doesn't. Can you confirm if the same applies to the MG21/21E? - Power Adapter vs PoE : The MG can be powered using a PoE or via a power adapter. The power adapter always takes the first preference i.e if the MG is already powered via the PoE and then the power adapter is connected, then the MG will power off and power on using the adapter as the power source. The same scenario applies when the PoE and power adapter are connected simultaneously and the power source from the adapter goes down, the MG will power off and then power on. Plugging/unplugging PoE when power adapter is connected to the MG does not have any bearing on the operation of the MG as the device will always draw power from the adapter whenever it is connected.
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