Layer 2 broadcasts, NIC, Subnets

AndrewsBoots

Need help guys, I'm caught up on a minor detail I hope.

From Switch1 configured with vlan1 ip address 192.168.1.2/24 I can not ping Host0 192.168.2.1/16

When the frame reaches Switch0 with an unknown destination MAC, Switch0 will broadcast the frame, which will then reach Host0. Why is Host0 not replying?

When I change Switch1's subnet mask to /24, the ping is successful.

Shouldn't the NIC reply to the source mac address? which is listed under the Host0 ARP table

Host0:ipconfig /all
Physical Address................: 000B.BE97.68B4
IP Address......................: 192.168.2.1
Subnet Mask.....................: 255.255.0.0
Default Gateway.................: 0.0.0.0
DNS Servers.....................: 0.0.0.0

Switch0#sho run
Building configuration...

Current configuration : 875 bytes
!
version 12.1
no service password-encryption
!
hostname Switch0
!
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
omitted for brevity

interface Vlan1
ip address 192.168.1.1 255.255.0.0
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
end

Switch1#sho run
Building configuration...

Current configuration : 877 bytes
!
version 12.1
no service password-encryption
!
hostname Switch1
!
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
omitted for brevity
!
interface Vlan1
ip address 192.168.1.2 255.255.255.0
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
end



Is the host not replying because the request is from outside its subnet? Or is my configuration just whacked?

networker050184

Yes it is because its on a different subnet. Once the host sees the destination is not in its own subnet it will send it to its default gateway.

nel

networker050184 wrote:

Yes it is because its on a different subnet. Once the host sees the destination is not in its own subnet it will send it to its default gateway.

Its like networker said. If you change your host to an IP in the same subnet your ping will be successful.

If you wanted to use different subnets with several vlans you then start to use inter vlan routing or L3switches to route between the subnets.