Why can I ping in one direction but not the other????

[Guest]

I can connect to my desktop with one of my laptops, but not the other way
around. I am going through a Linksys router (used with VOIP) to a Netgear
router which is my DHCP. I can ping the desktop (192.168.0.6) with the
Laptop and can see the shared folders and copy to and from the desktop. I
CANNOT ping or connect from the desktop to the laptop (192.168.15.100). I use
the free ZoneAlarm and the laptop is in the trusted zone along with the
Linksys router. I can disable ZoneAlarm and get the same results.

Anybody got a clue?? What am I missing?

Thanks for the help.

 

[Chuck]

I can connect to my desktop with one of my laptops, but not the other way
around. I am going through a Linksys router (used with VOIP) to a Netgear
router which is my DHCP. I can ping the desktop (192.168.0.6) with the
Laptop and can see the shared folders and copy to and from the desktop. I
CANNOT ping or connect from the desktop to the laptop (192.168.15.100). I use
the free ZoneAlarm and the laptop is in the trusted zone along with the
Linksys router. I can disable ZoneAlarm and get the same results.

Anybody got a clue?? What am I missing?

Thanks for the help.

The desktop (192.168.0.6) and the laptop (192.168.15.100) are in two separate
subnets. How are the two subnets connected? Is the desktop attached to the
Netgear, with the WAN side of the Linksys attached there too?

If that's not it, please try and describe in more detail how everything
connects. This article might be of use:
<http://nitecruzr.blogspot.com/2005/05/troubleshooting-network-neighborhood.html>

--
Cheers,
Chuck
http://nitecruzr.blogspot.com/
Paranoia is not necessarily a bad thing - it's a normal response from experience.
My email is AT DOT
actual address pchuck sonic net.

 

[Ron Lowe]

I can connect to my desktop with one of my laptops, but not the other way
around. I am going through a Linksys router (used with VOIP) to a Netgear
router which is my DHCP. I can ping the desktop (192.168.0.6) with the
Laptop and can see the shared folders and copy to and from the desktop. I
CANNOT ping or connect from the desktop to the laptop (192.168.15.100). I
use
the free ZoneAlarm and the laptop is in the trusted zone along with the
Linksys router. I can disable ZoneAlarm and get the same results.

Anybody got a clue?? What am I missing?

Thanks for the help.

Are they both getting addresses from the router?

What range of addresses is the router set up to issue?
What subnet mask is it issuing?

Assuming the subnet masks in use are 255.255.255.0,
then the machines are not in the same subnet.

One address is in the 192.168.0.x range, whilst the other is in
the192.168.15.x range.
That's unusual.

I'd expect the first 3 octets to be the same in this kind of setup.
eg: all 192.168.0.x

 

[Ron Lowe]

I can connect to my desktop with one of my laptops, but not the other way
around. I am going through a Linksys router (used with VOIP) to a Netgear
router which is my DHCP. I can ping the desktop (192.168.0.6) with the
Laptop and can see the shared folders and copy to and from the desktop. I
CANNOT ping or connect from the desktop to the laptop (192.168.15.100). I
use
the free ZoneAlarm and the laptop is in the trusted zone along with the
Linksys router. I can disable ZoneAlarm and get the same results.

Anybody got a clue?? What am I missing?

Thanks for the help.

Considering further, the subnets ( odd as they are ) can't be the issue.
If they can ping in one direction, then there's a route there, and a route
back.

In that case, it's probably a firewall issue on the laptop.

Is the desktop in the trusted zone on the laptop?

Perhaps time to un-install firewalls untill you get it figured out.
Use the instructions on ZoneLabs site to un-install, don't just do it from
add/remove programs.

 

[Guest]

:

The desktop (192.168.0.6) and the laptop (192.168.15.100) are in two separate
subnets. How are the two subnets connected? Is the desktop attached to the
Netgear, with the WAN side of the Linksys attached there too?

If that's not it, please try and describe in more detail how everything
connects. This article might be of use:
<http://nitecruzr.blogspot.com/2005/05/troubleshooting-network-neighborhood.html>

Hey Chuck. The above link would not work.

The desktop is connected to the Netgear. The Linksys is connected to the
Netgear. the laptop is connected to the Linksys. The subnet is
255.255.255.0 on both machines.

 

[Guest]

Are they both getting addresses from the router?

What range of addresses is the router set up to issue?
What subnet mask is it issuing?

Assuming the subnet masks in use are 255.255.255.0,
then the machines are not in the same subnet.

One address is in the 192.168.0.x range, whilst the other is in
the192.168.15.x range.
That's unusual.

I'd expect the first 3 octets to be the same in this kind of setup.
eg: all 192.168.0.x

Ron, the subnets are 255.255.255.0 on both machines. The desktop is
connected to the Netgear and gets its IP address from it. The Linksys is
connected to the Netgear and the laptop gets its address from the Linksys.
The Netgear is connected to a DSL modem. The laptop accesses the internet
fine (thru the Linksys to the Netgear to the modem).

Have to use the Linksys (which is also a VOIP phone adaptor) because all the
ports on the Netgear router are in use.

 

[Guest]

Considering further, the subnets ( odd as they are ) can't be the issue.
If they can ping in one direction, then there's a route there, and a route
back.

In that case, it's probably a firewall issue on the laptop.

Is the desktop in the trusted zone on the laptop?

The desktop is in the trusted zone on the laptop and the laptop can access
the desktop fine with the ZoneAlarm firewall on.

The laptop is in the trusted zone on the desktop as well.

Perhaps time to un-install firewalls untill you get it figured out.
Use the instructions on ZoneLabs site to un-install, don't just do it from
add/remove programs.

I disabled the ZoneAlarms on both machines to see if it made a difference
and it didn't.

Steve

 

[Ron Lowe]

Ron, the subnets are 255.255.255.0 on both machines. The desktop is

connected to the Netgear and gets its IP address from it. The Linksys is
connected to the Netgear and the laptop gets its address from the Linksys.
The Netgear is connected to a DSL modem. The laptop accesses the internet
fine (thru the Linksys to the Netgear to the modem).

Have to use the Linksys (which is also a VOIP phone adaptor) because all
the
ports on the Netgear router are in use.

AHH!

You have a double NAT configuration.

DSL
|
Netgear NAT Router -- Desktop
|
Linksys NAT Router
| |
Laptop VoIP phones



That's not going to work!
The laptop can ping the desktop, because it's an outbound connection through
the linksys NAT.
The desktop can't connect to the laptop because the NAT drops the
unsolicited inbound connection.

You need to connect the laptop to the netgear directly.
I know you said it's out of ports, but by directly I mean not via a router.
You can keep the linksys if you need it for VoIP.
Just don't use it for your LAN!
An additional switch is required.

DSL
|
Netgear NAT Router -- New Switch
| | |
Linksys NAT Laptop Desktop
Router
|
VoIP phones



Now, the laptop and desktop will both get 192.168.0.x addresses from the
Netgear.

 

[Gerald Vogt]

AHH!

You have a double NAT configuration.
...
You need to connect the laptop to the netgear directly.
I know you said it's out of ports, but by directly I mean not via a router.
You can keep the linksys if you need it for VoIP.
Just don't use it for your LAN!
An additional switch is required.

Well, it depends. I don't see the reason, why you would run NAT on the
Linksys anyway. Don't run the Linksys as gateway but as router and setup
routes on both routers. Then you are able to have traffic in both
directions.

Else, if you have two spare ports on the Linksys, it may be enough to
plug in the uplink (the on in the Linksys WAN port) into one of the LAN
ports.

Everything kind of depends though on which hardware you use...

Gerald

 

[Harry Putnam]

Ron, the subnets are 255.255.255.0 on both machines. The desktop is

Nobody seems to have pointedout that the above is a netmask not a
subnet. Clearing that up may bring more clarity.
The subnets presented so far are 192.168.0.0 and 192.168.15.0

So unless there is a gateway between those two subnets they won't
communicate.

You could try setting a manual ip on the laptop in 192.168.0.(1-254)
Somewhere between 1 and 254 but try to pick a number known not to be
in use.

 

[Star Fleet Admiral Q]

I agree with Ron on that one, I too have a similar setup using 2 Linksys
routers, one in DHCP mode, one just acting as a switch, but all connections
are still using the same 1st 3 octet combo, handed out by the Linksys
connected to the Cable Modem.

--

Star Fleet Admiral Q @ your Service!

http://www.google.com
Google is your "Friend"

 

[Ron Lowe]

Well, it depends. I don't see the reason, why you would run NAT on the
Linksys anyway. Don't run the Linksys as gateway but as router and setup
routes on both routers. Then you are able to have traffic in both
directions.

Yes, at a pure IP level, you could turn off NAT on the linksys,
and set up static routing between 2 subnets,
but I can't think of a good reason to do that in this case.
Several things will still not work.

Broadcast-based NetBIOS name resolution will fail between the subnets.
Broadcast-based browsing fill aslo fail between the subnets.

If you want to make a windows network function across subnets,
then you need a name resolution service like WINS or DNS in place.
(or you need to mess with hosts / lmhosts files )

Futher, if you want to make NetBIOS browsing function across subnets,
then you also really need a Domain.
This provides for a Domain master browser, which collates browse-lists
from the individual segment master browsers, and re-distributes the merged
browse list back out to the segments.

In short, a simple peer-to-peer windows network ( without WINS / DNS /
Domain ) really functions best on a single local subnet. That's why I
reccomended moving all the windows machines to the same subnet, by using a
switch to extend the number of ports available on the netgear device.

 

[Gerald Vogt]

In short, a simple peer-to-peer windows network ( without WINS / DNS /
Domain ) really functions best on a single local subnet. That's why I
reccomended moving all the windows machines to the same subnet, by using a
switch to extend the number of ports available on the netgear device.

Well, as a complete peer-to-peer is not working now either, I thought
the solution should be inexpensive and thus a solution without new
hardware was preferable. Fixing the problem with minimal effort.

It kind of depends on the budget and the requirements of what you want
to have...

Gerald

 

[Ron Lowe]

Well, as a complete peer-to-peer is not working now either, I thought the
solution should be inexpensive and thus a solution without new hardware
was preferable. Fixing the problem with minimal effort.

It kind of depends on the budget and the requirements of what you want to
have...

Gerald

His peer-to-peer network would continue to not work
across the static router for the reasons I outlined.
( no name resolution, no browsing. )

A possible no-new-hardware solution would be to use the linksys as
neither a NAT device OR a static IP router, but simply as a switch.

We couldUplink from one of the linksys LAN ports to the Netgear,
leaving the linksys WAN port unused. Also, we'd ensure DHCP
server is off on the linksys, allowing all DHCP to come from the netgear.

I chose not to reccommend this, because I didn't want to mess with the
exsisting VoIP configuration on the linksys, which is working.
I thought it best to leave that as-is.