Routing Basics Question
Dear All,
Suppose
PC1 : 192.168.10.10 - default gateway : 192.168.10.1
SRV1: 172.16.10.200
PC1 Wants to reach SRV1, hence the first thing that PC1 will do is an ARP to know the MAC table of the DST (SRV1). PC1 will get no reponse , to this point everything is gr8. But what happens after that between PC1 and default gateway? when does the ARP proxy take place ?
This is a relatively long process...so I'm going to recommend that you watch an episode here:
Aubri and I cover the entire process of this process works in detail.
@Ronnie-Wong I actually did, but i got confused in step 1. You have mentioned that the PC will send an ARP and it will get no response, after that you mention that the router replies with a proxy ARP . So how there is a proxy ARP , but at the same time none replied PC1 ?
Or does the PC does the ARP request twice ?
A PC sends to a destination on another network. It looks it up in its own routing table. When there is no matching layer 3 address in that routing table, it will match it the "default gateway" which is typically the ip address of the router leading out of your LAN.
Does the router have the MAC address of that destination machine...if it's not a router..highly unlikely. So the router instead sends the PC its MAC address instead of the destination MAC address--a proxy mac address. This way your PC1 can forward the frame to the router. The router then can look up the IP address in the routing table to forward your frame to the next router.
