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How computer Arp Table gets populated.

How computer Arp Table gets populated.

I would like to know How computer Arp Table gets populated..
for instance on my computer I see Dynamic and Static entries, the Static entries are all Multicats range , the 224 and 239.
for The Dynamic entries, I see some IP addresses on the same subnet as my computer, but other IP addresses are on the same subnet as my Default Gateway subnet.

So how do they get populated?
if I ping a computer on the other VLAN, then run arp -a , I cannot see its IP address in the ARp table.

Any clarification on this ?

Thank you
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arp -a will show only the IPs that are in the same subnet as my computer Default Gateway, or in the same subnet as my computer IP address.

For instance.

My computer is 10.10.10.46/24 its DG: 10.10.12.1/24

if I ping any computer in 10.10.10.0 I can find it in arp table using arp -a command

If I if I ping any computer in 10.10.12.0 I can find it in arp table using arp -a command

but if I ping any computer in 10.10.13.0 I cannot find it in arp table using arp -a command
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noci

or you need to check the routing table and will find the mac address of the gateway in the arp  table.
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sorry
> My computer is 10.10.10.46/24 its DG: 10.10.12.1/24 : Not Correct

 My computer is 10.10.10.46/23 its DG: 10.10.12.1
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And I pinged a host  10.10.12.66  (Which in the same subnet as my DG), then after I ran arp -a , I saw the 10.10.12.66 with a corresponding MAC accress
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Sorry , Sorry ...
PC= 10.10.211.46/23
DG= 10.10.210.1



So DG subnet should be covered by the subnet where the PC is.

/23 will include : 10.10.192.0 to 10.10.255.255
The DG ip : 10.10.210.1 is already inside  the range /23  10.10.192.0 to 10.10.255.255
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how did you come with this ?

10.10.210.0/23 would have a range of:
10.10.210.1 - 10.10.211.254
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Oh... and one piece I didn't spell out.  The /23 is the number of 1 bits in the subnet mask being:
mask   1111 1111.1111 1111.1111 1110.0000 0000  = 23 bits on in the mask.
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Thank you Guys