1 MAC, 2 IPs on LAN

Hi. Yes this is famous dilemma for how MAC should be unique but I have the following situation and want to know what is happening in real.

I've added on my laptop 2 IP addresses to the same NIC
10.0.0.2 and 10.0.0.3 on the same subnet.

Now the AP has 10.0.0.1.
On the AP i executed "ping 10.0.0.2 & ping 10.0.0.3" and it was all fine without drops !
Now I entered "arp -a" and saw 10.0.0.2 and 10.0.0.3 having the same MAC.

Is this okay because I need multiple LAN ips on the same NIC ?
How is it not failing ? In the past I discovered that it is possible that for example 10.0.0.1 when pinging 10.0.0.3 actually pings 10.0.0.2 because of "arp_proxy" mechanism (but I dunno if that's the case).

Will this be ok or I will have major consequences probably on TCP/UDP & others as ping is ICMP protocol..?

It should be OK. Usually the additional IPs are something normal, but often used for different networks. If configured this way, I don't think you need the proxy ARP. The interesting part is if you need to originate the outgoing traffic via the same IP - is the PC going to use the IP of the incoming connection or the primary IP, since in the same network... So I think it depends over the laptop's OS implementation.

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