Why should a host and its GW (network gateway) be in the same L2 domain (in the same vlan)?

Question

Computer networks

Please help me to sort out this issue.

Answer 1

Imagine the reverse situation - the host and its gateway are NOT within the same network. Then, obviously, in order to send a packet to the gateway, some node in the network is required, routing packets outside of it. Hop, you've got a new gateway.

Answer 2

Read about Ethernet frames, how ARP works, why you need a broadcast address and you will understand.

Answer 3

https://linkmeup.ru/sdsm/
read until understanding....
As well as Oliferov, etc......