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Why No MAC Address?

I've had to create VLANs.  Prior to making the changes, I got IP and MAC information.  Since I implemented the VLANs Advanced IP can ping devices on another VLAN, but no longer reports the MAC address for those devices.


What could cause that?
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0
09/30/2019
Hello,

MAC-address is not shown while scanning other subnet.
0
09/30/2019
Thank you for your response,


I'm not sure that being in a different subnet is to root cause.


The strange is that prior to introducing VLANs, I was able to see MAC addresses on different subnets.  A workstation on the 192.168.2.0 /24 network would scan 192.168.5.0 /24.  Devices would respond do the ping and display the MAC.  


Formally, data from those networks was being managed by a SonicWALL firewall.  The change I've made was to introduce a Layer3 switch and making that the gateway for the various networks.  The switch uses the firewall as it's gateway of last resort.  


I'm wondering if the local firewall on the Windows devices, would be preventing Advanced IP from seeing the MAC address.  But  the MAC is Layer 2 data.  Also it is in front of the VLAN ID info in the Ethernet frame.
0
10/01/2019
Hello,

Run in Command line
arp -a IP
where IP is the device IP address. If it wont return MAC, it shows that AIPS is not able to do this too.
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