Ping is broken...

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
Hi all,

We have stores all over the country each with their own PC with 3G card, connecting via a Billion router with a VPN connection.

At a few of the stores I have had a few issues - what it comes down to is that when I try to ping a server on the network at headoffice(i.e. exchange) the ping resolves the correct IP - but then it replies from a different IP.

Below is what I get when running such a ping...does anyone have any ideas as to what the problem might be?


C:\Documents and Settings\administrator>ping ***ex

Pinging ***ex.********.com [192.168.0.10] with 32 bytes of data:

Reply from 192.168.0.19: bytes=32 time=148ms TTL=126
Reply from 192.168.0.19: bytes=32 time=123ms TTL=125
Reply from 192.168.0.19: bytes=32 time=124ms TTL=125
Reply from 192.168.0.19: bytes=32 time=125ms TTL=125

Ping statistics for 192.168.0.10:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 123ms, Maximum = 148ms, Average = 130ms

:confused::confused:
 
Last edited:

adielh

Well-Known Member
Joined
Jul 29, 2009
Messages
379
It gets directed from a proxy that's why its a different address
 

adielh

Well-Known Member
Joined
Jul 29, 2009
Messages
379
oh Ya dude never give you IP on a forum ,there are strange people out there
 

MadMailMan

Expert Member
Joined
Nov 1, 2006
Messages
2,209
oh Ya dude never give you IP on a forum ,there are strange people out there

Not really a problem, guess you didn't notice that it's inside his VPN and it's a private address (192.168.x.x).

Is your exchange box behind another firewall. You can configure certain firewalls to reply to ping/tracert/etc for the entire network behind it. Try telnetting in on port 25 and see if you can connect. Have you worked out what the device is that is replying? Is it a router? If yes it may need a bounce, or check it's logs to see what it thinks it is doing.
 
Last edited:

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
hey adielh...

are you talking about an internet proxy?

why is it that i get replies from other servers on my network from their own IP's, but only this one replies from another IP?
 

gregmcc

Honorary Master
Joined
Jun 29, 2006
Messages
23,119
What servers are on .10 and .19. If you traceroute to them to the both go via the same network?
You might have some ARP poisoning - if 2 IP's had the same MAC they could response with something similiar?
 

Conradl

Expert Member
Joined
Dec 10, 2008
Messages
2,630
OS?? Is your firewall service running? Vista/2008/Win7 does what you describe if you turn off the firewall....
 

werner

Expert Member
Joined
Jun 27, 2005
Messages
3,396
your firewall device needs to support 1:1 nat so you can assign a specific external ip to map to an internal ip for outbound traffic.

in your scenario above, the dns name resolves to the correct machine, which has icmp etc port forwarded by the looks of it correctly, but the reply is coming via the visible external ip, which in this case is also in the 192 range (external, as in from the box viewpoint, not from the whole internet ...so probably a firewall or gateway device)

if you have iptables installed, then have a look at SNAT for the .10 machine
 

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
.10 would be the local machine IP (in the store connected via 3G & VPN so it has a local address - each store has its own subnet) and .19 would be the ISA box - our headoffice firewall.

what confuses me further is that it used to work up to a while ago, and from then the exchange ping replies with the firewall IP.

the store machines are running winXP
the firewall is on Win Server 2003
and the exchange box is on Win Server 2008
 

Conradl

Expert Member
Joined
Dec 10, 2008
Messages
2,630
Have you checked that the firewall service is running on your exchange server? I have the exact same problem with 2008 machines....
 

adielh

Well-Known Member
Joined
Jul 29, 2009
Messages
379
Hi Galaxy ,

Tel me if I'm correct, you guys are running windows terminal server with dhcp mode , with Remote vpn to logg on to the sever from any branch,using terminal session?? You have a Radius mail and domain server, all incl in the terminal server,
 

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
Hi Conradl, the firewall is indeed on. but why do i only experience this problem from one of the stores? all other stores ping the exchange on its correct IP.

Hi adielh, no. each site has a Billion router which acts as a DCHP(and is setup with the VPN connection - which runs over a 3G connection). each store has a machine(connected to the router via UTP cable) with a SQL DB on which they capture their data and this SQL replicates every evening. if need be i terminal into the store machine to provide support. hope that answers your question...
 

adielh

Well-Known Member
Joined
Jul 29, 2009
Messages
379
wow i run the same setup, but its flawless using terminal server. Currently I run that setup with a VMware , so its hassle free
 

adielh

Well-Known Member
Joined
Jul 29, 2009
Messages
379
Well it could also be that those pc run vista , and have IPv4 and ipV6 addresses which your dhcp cannot assign, and give a default router address
 

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
hehe...nice.

all the store machines run Windows XP. the router serves as the DHCP on each subnet and it assigns itself as the Default Gateway on that specific subnet.
 

GalaxyAdmin

New Member
Joined
Aug 17, 2009
Messages
9
hey all...thank you for your input & ideas. i have managed to fix the problem with the assistance of a rather clever oke. it was a routing problem, after adding the routes the pings went through to the correct IP & I was able get the data where it needed to go.

once again...thank you
 
Top