Network Ping issue

[Evo 0]

Hi All

 

We have just moved into a new office and I will be installing IP cameras in various locations around the building. I am just getting my feet wet in terms of understanding the network and and have started by plugging 2 computers into the network. The first is 192.168.18.15 (Comp 1) and the second is 192.168.18.16 (Comp 2).

 

Im trying to establish if all my ports in the building can see each other in the long term and there are no VPN type things going on.

 

So anyway. When I ping 192.168.18.15 (Comp 1) using PC 192.168.18.16 (Comp 2) i dont get a response BUT when I ping 192.168.1.16 (Comp 2) from 192.168.18.15 (Comp 1) I do get a reply. So one can ping the other but not the other way round.

 

Now when I type ARP -a in 192.168.18.16 (Comp 2) I can see 192.168.18.15 (Comp 1) on the network, but I cant ping it??

 

Any ideas why that would happen??

 

Thankyou!

 

Gaz

 

[buellwinkle 0]

Make sure the gateway addresses on both are correct and the same.

[Securame 0]

Computer with IP 15 might have some kind of firewall or antivirus installed that is not allowing the machine to receive/reply ping requests (Windows firewall, Norton, McAfee, etc).

[mkkoskin 0]

By default Windows 7 rejects all ping packets if firewall is enabled, try disabling the firewall from all Windows machines before attempting any pinging. I've spent few hours around this in the past aswell

 

Here is few links to guides on how to enable the ping response:

http://answers.microsoft.com/en-us/windows/forum/windows_7-networking/how-to-enable-ping-response-in-windows-7/5aff5f8d-f138-4c9a-8646-5b3a99f1cae6

http://www.sysprobs.com/enable-ping-reply-windows-7

[atari37 0]

As stated above, Windows 7 and up disables ICMP packets by default. Allow it via the firewall.

 

Quick way to test this will be to disable the Windows firewall.