Remote Desktop connection bombs out when VPN initiated

Hi Guys,

My knowledge about networking is very basic since i am a software guy and my
question is VPN related, when i am remote desktoped into my home machine from
outsite the network and then onnect VPN to my office network, i am kicked out
of remote desktop connect and can not connect back to the machine over remote
desktop as long as the VPN is running, if i disconnect the VPN and connect
again, i am in. Here are the details:

Home machine : Windows XP Pro.
LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
automatically.
Home network Setup: i have a comcast router\ filewall which bring in
comcast internet connection. From the comcast the cable to my lingo ( voice
over ip) router. From the lingo router it then goes to my Computer.

Comcast router gives out IP in the range : 10.1.10.**
Lingo router in the range : 172.125.25.**
My machine is configured to obtain an IP and DNS automatically from the
lingo router and it gives it 172.25.25.2 all the time.

I configured my comcast and lingo router to pass on the Remote desktop
request comming from the public IP to my machine and it works great. But the
problem is that after i Remote desktop into my machine from outsite the
network, if i connect to the VPN of my office network then remote destop
bombs out and i cannot connect to my mahcine from outsite any more. After the
VPN is connected when i do an ipconfig of my machine, my machine now has two
IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the other
IP 192.168.168.* that my office DNS server assigns and i think this is where
my comcast and lingo routers get confused and not connect request comming for
remotedesktop to my machine.

so the question is how can i configure my comcast\ lingo router or my
machine so that even when my home machine is connected over VPN to my office
network i can Remote dektop into it.

waiting for an answer.

thanks
sameer

This problem I have seen before and reducing the size of the MTU solved the
problem. I don´t say it will solve your problem, but you might want to try
this.

--
----------------------------------------------------------------------------------------------------------------------------
Johan Engdahl
CCSA, CCSE, CCA, MCP | johan AT firewall1 DOT nu | http://www.firewall1.nu

"sameer" <(E-Mail Removed)> wrote in message
news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
> Hi Guys,
>
> My knowledge about networking is very basic since i am a software guy and
> my
> question is VPN related, when i am remote desktoped into my home machine
> from
> outsite the network and then onnect VPN to my office network, i am kicked
> out
> of remote desktop connect and can not connect back to the machine over
> remote
> desktop as long as the VPN is running, if i disconnect the VPN and connect
> again, i am in. Here are the details:
>
> Home machine : Windows XP Pro.
> LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
> automatically.
> Home network Setup: i have a comcast router\ filewall which bring in
> comcast internet connection. From the comcast the cable to my lingo (
> voice
> over ip) router. From the lingo router it then goes to my Computer.
>
> Comcast router gives out IP in the range : 10.1.10.**
> Lingo router in the range : 172.125.25.**
> My machine is configured to obtain an IP and DNS automatically from the
> lingo router and it gives it 172.25.25.2 all the time.
>
> I configured my comcast and lingo router to pass on the Remote desktop
> request comming from the public IP to my machine and it works great. But
> the
> problem is that after i Remote desktop into my machine from outsite the
> network, if i connect to the VPN of my office network then remote destop
> bombs out and i cannot connect to my mahcine from outsite any more. After
> the
> VPN is connected when i do an ipconfig of my machine, my machine now has
> two
> IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the
> other
> IP 192.168.168.* that my office DNS server assigns and i think this is
> where
> my comcast and lingo routers get confused and not connect request comming
> for
> remotedesktop to my machine.
>
> so the question is how can i configure my comcast\ lingo router or my
> machine so that even when my home machine is connected over VPN to my
> office
> network i can Remote dektop into it.
>
> waiting for an answer.
>
> thanks
> sameer
>
>
>
>
>

You can't do both at the same time efficiently or securely.
Just do one at a time.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com

The views expressed (as annoying as they are, and as stupid as they sound), are
my own and not those of my employer, or Microsoft, or anyone else associated
with me, including my cats.
-----------------------------------------------------


"sameer" <(E-Mail Removed)> wrote in message
news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
> Hi Guys,
>
> My knowledge about networking is very basic since i am a software guy and my
> question is VPN related, when i am remote desktoped into my home machine from
> outsite the network and then onnect VPN to my office network, i am kicked out
> of remote desktop connect and can not connect back to the machine over remote
> desktop as long as the VPN is running, if i disconnect the VPN and connect
> again, i am in. Here are the details:
>
> Home machine : Windows XP Pro.
> LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
> automatically.
> Home network Setup: i have a comcast router\ filewall which bring in
> comcast internet connection. From the comcast the cable to my lingo ( voice
> over ip) router. From the lingo router it then goes to my Computer.
>
> Comcast router gives out IP in the range : 10.1.10.**
> Lingo router in the range : 172.125.25.**
> My machine is configured to obtain an IP and DNS automatically from the
> lingo router and it gives it 172.25.25.2 all the time.
>
> I configured my comcast and lingo router to pass on the Remote desktop
> request comming from the public IP to my machine and it works great. But the
> problem is that after i Remote desktop into my machine from outsite the
> network, if i connect to the VPN of my office network then remote destop
> bombs out and i cannot connect to my mahcine from outsite any more. After the
> VPN is connected when i do an ipconfig of my machine, my machine now has two
> IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the other
> IP 192.168.168.* that my office DNS server assigns and i think this is where
> my comcast and lingo routers get confused and not connect request comming for
> remotedesktop to my machine.
>
> so the question is how can i configure my comcast\ lingo router or my
> machine so that even when my home machine is connected over VPN to my office
> network i can Remote dektop into it.
>
> waiting for an answer.
>
> thanks
> sameer
>
>
>
>
>

Johan, what is a MTU ?? and how to reduce it.

"Johan Engdahl" wrote:

> This problem I have seen before and reducing the size of the MTU solved the
> problem. I don´t say it will solve your problem, but you might want to try
> this.
>
> --
> ----------------------------------------------------------------------------------------------------------------------------
> Johan Engdahl
> CCSA, CCSE, CCA, MCP | johan AT firewall1 DOT nu | http://www.firewall1.nu
>
> "sameer" <(E-Mail Removed)> wrote in message
> news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
> > Hi Guys,
> >
> > My knowledge about networking is very basic since i am a software guy and
> > my
> > question is VPN related, when i am remote desktoped into my home machine
> > from
> > outsite the network and then onnect VPN to my office network, i am kicked
> > out
> > of remote desktop connect and can not connect back to the machine over
> > remote
> > desktop as long as the VPN is running, if i disconnect the VPN and connect
> > again, i am in. Here are the details:
> >
> > Home machine : Windows XP Pro.
> > LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
> > automatically.
> > Home network Setup: i have a comcast router\ filewall which bring in
> > comcast internet connection. From the comcast the cable to my lingo (
> > voice
> > over ip) router. From the lingo router it then goes to my Computer.
> >
> > Comcast router gives out IP in the range : 10.1.10.**
> > Lingo router in the range : 172.125.25.**
> > My machine is configured to obtain an IP and DNS automatically from the
> > lingo router and it gives it 172.25.25.2 all the time.
> >
> > I configured my comcast and lingo router to pass on the Remote desktop
> > request comming from the public IP to my machine and it works great. But
> > the
> > problem is that after i Remote desktop into my machine from outsite the
> > network, if i connect to the VPN of my office network then remote destop
> > bombs out and i cannot connect to my mahcine from outsite any more. After
> > the
> > VPN is connected when i do an ipconfig of my machine, my machine now has
> > two
> > IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the
> > other
> > IP 192.168.168.* that my office DNS server assigns and i think this is
> > where
> > my comcast and lingo routers get confused and not connect request comming
> > for
> > remotedesktop to my machine.
> >
> > so the question is how can i configure my comcast\ lingo router or my
> > machine so that even when my home machine is connected over VPN to my
> > office
> > network i can Remote dektop into it.
> >
> > waiting for an answer.
> >
> > thanks
> > sameer
> >
> >
> >
> >
> >
>
>
>

Phillip, please explain your self in a little detail?

"Phillip Windell" wrote:

> You can't do both at the same time efficiently or securely.
> Just do one at a time.
>
> --
> Phillip Windell [MCP, MVP, CCNA]
> www.wandtv.com
>
> The views expressed (as annoying as they are, and as stupid as they sound), are
> my own and not those of my employer, or Microsoft, or anyone else associated
> with me, including my cats.
> -----------------------------------------------------
>
>
> "sameer" <(E-Mail Removed)> wrote in message
> news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
> > Hi Guys,
> >
> > My knowledge about networking is very basic since i am a software guy and my
> > question is VPN related, when i am remote desktoped into my home machine from
> > outsite the network and then onnect VPN to my office network, i am kicked out
> > of remote desktop connect and can not connect back to the machine over remote
> > desktop as long as the VPN is running, if i disconnect the VPN and connect
> > again, i am in. Here are the details:
> >
> > Home machine : Windows XP Pro.
> > LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
> > automatically.
> > Home network Setup: i have a comcast router\ filewall which bring in
> > comcast internet connection. From the comcast the cable to my lingo ( voice
> > over ip) router. From the lingo router it then goes to my Computer.
> >
> > Comcast router gives out IP in the range : 10.1.10.**
> > Lingo router in the range : 172.125.25.**
> > My machine is configured to obtain an IP and DNS automatically from the
> > lingo router and it gives it 172.25.25.2 all the time.
> >
> > I configured my comcast and lingo router to pass on the Remote desktop
> > request comming from the public IP to my machine and it works great. But the
> > problem is that after i Remote desktop into my machine from outsite the
> > network, if i connect to the VPN of my office network then remote destop
> > bombs out and i cannot connect to my mahcine from outsite any more. After the
> > VPN is connected when i do an ipconfig of my machine, my machine now has two
> > IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the other
> > IP 192.168.168.* that my office DNS server assigns and i think this is where
> > my comcast and lingo routers get confused and not connect request comming for
> > remotedesktop to my machine.
> >
> > so the question is how can i configure my comcast\ lingo router or my
> > machine so that even when my home machine is connected over VPN to my office
> > network i can Remote dektop into it.
> >
> > waiting for an answer.
> >
> > thanks
> > sameer
> >
> >
> >
> >
> >
>
>
>

Maybe this will help you:

http://support.microsoft.com/kb/826159

--
----------------------------------------------------------------------------------------------------------------------------
Johan Engdahl
CCSA, CCSE, CCA, MCP | johan AT firewall1 DOT nu | http://www.firewall1.nu

"sameer" <(E-Mail Removed)> wrote in message
news:FC04D7F4-4988-44DE-9C89-(E-Mail Removed)...
> Johan, what is a MTU ?? and how to reduce it.
>
> "Johan Engdahl" wrote:
>
>> This problem I have seen before and reducing the size of the MTU solved
>> the
>> problem. I don´t say it will solve your problem, but you might want to
>> try
>> this.
>>
>> --
>> ----------------------------------------------------------------------------------------------------------------------------
>> Johan Engdahl
>> CCSA, CCSE, CCA, MCP | johan AT firewall1 DOT nu |
>> http://www.firewall1.nu
>>
>> "sameer" <(E-Mail Removed)> wrote in message
>> news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
>> > Hi Guys,
>> >
>> > My knowledge about networking is very basic since i am a software guy
>> > and
>> > my
>> > question is VPN related, when i am remote desktoped into my home
>> > machine
>> > from
>> > outsite the network and then onnect VPN to my office network, i am
>> > kicked
>> > out
>> > of remote desktop connect and can not connect back to the machine over
>> > remote
>> > desktop as long as the VPN is running, if i disconnect the VPN and
>> > connect
>> > again, i am in. Here are the details:
>> >
>> > Home machine : Windows XP Pro.
>> > LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
>> > automatically.
>> > Home network Setup: i have a comcast router\ filewall which bring in
>> > comcast internet connection. From the comcast the cable to my lingo (
>> > voice
>> > over ip) router. From the lingo router it then goes to my Computer.
>> >
>> > Comcast router gives out IP in the range : 10.1.10.**
>> > Lingo router in the range : 172.125.25.**
>> > My machine is configured to obtain an IP and DNS automatically from the
>> > lingo router and it gives it 172.25.25.2 all the time.
>> >
>> > I configured my comcast and lingo router to pass on the Remote desktop
>> > request comming from the public IP to my machine and it works great.
>> > But
>> > the
>> > problem is that after i Remote desktop into my machine from outsite the
>> > network, if i connect to the VPN of my office network then remote
>> > destop
>> > bombs out and i cannot connect to my mahcine from outsite any more.
>> > After
>> > the
>> > VPN is connected when i do an ipconfig of my machine, my machine now
>> > has
>> > two
>> > IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the
>> > other
>> > IP 192.168.168.* that my office DNS server assigns and i think this is
>> > where
>> > my comcast and lingo routers get confused and not connect request
>> > comming
>> > for
>> > remotedesktop to my machine.
>> >
>> > so the question is how can i configure my comcast\ lingo router or my
>> > machine so that even when my home machine is connected over VPN to my
>> > office
>> > network i can Remote dektop into it.
>> >
>> > waiting for an answer.
>> >
>> > thanks
>> > sameer
>> >
>> >
>> >
>> >
>> >
>>
>>
>>

If I can,...I don't know...others are welcomed to fill in any "gaps" I leave.

The network that receives the incoming VPN connection is considered to be "at
risk" from the VPN Client who can present certain risks. So there are
characteristics about the "dialup" technology that are built into it to mitigate
some of the risk.
VPN (Remote Access VPN, that is) is considered a "dialup technology" and follows
many of the behavor patterns of the old modem dialup situations.

When a Remote Access VPN Connection is established:
1. The Virtual Dialup Adapter (the VPN Adapter) becomes the primary interface
for the machine,...the physical Nic no longer is.
2. The Dialup Connection (the VPN Connection) becomes the Default Route for the
machine making the "call". This is associated somehow with the Default Gateway
of the subnet being "dialed into" which is the subnet associated with the TCP/IP
specs that the dialing Client received when the connection was established.

The purpose is to isolate Client from other networks and other connection
sources during the period that it is connected via the VPN to the LAN. This is
also how the VPN Client is able to connect to other subnets on the LAN over the
VPN when normally it would only be "aware" of the immediate subnet it connected
to, but nothing beyond that.

This characteristic can be disabled, but will eliminate the ability to use
multiple subnets on the LAN it dialed into, and also put the LAN it dial into at
risk from whatever the Client may be connected to with any of its other
interfaces. Disabling that functionality and running without it is called
"Split-Tunneling". Split-Tunneling is considered undesirable and a security
risk.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com

The views expressed (as annoying as they are, and as stupid as they sound), are
my own and not those of my employer, or Microsoft, or anyone else associated
with me, including my cats.
-----------------------------------------------------


"sameer" <(E-Mail Removed)> wrote in message
news:7E39E2DC-181B-4E4A-95D0-(E-Mail Removed)...
> Phillip, please explain your self in a little detail?
>
> "Phillip Windell" wrote:
>
>> You can't do both at the same time efficiently or securely.
>> Just do one at a time.
>>
>> --
>> Phillip Windell [MCP, MVP, CCNA]
>> www.wandtv.com
>>
>> The views expressed (as annoying as they are, and as stupid as they sound),
>> are
>> my own and not those of my employer, or Microsoft, or anyone else associated
>> with me, including my cats.
>> -----------------------------------------------------
>>
>>
>> "sameer" <(E-Mail Removed)> wrote in message
>> news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
>> > Hi Guys,
>> >
>> > My knowledge about networking is very basic since i am a software guy and
>> > my
>> > question is VPN related, when i am remote desktoped into my home machine
>> > from
>> > outsite the network and then onnect VPN to my office network, i am kicked
>> > out
>> > of remote desktop connect and can not connect back to the machine over
>> > remote
>> > desktop as long as the VPN is running, if i disconnect the VPN and connect
>> > again, i am in. Here are the details:
>> >
>> > Home machine : Windows XP Pro.
>> > LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
>> > automatically.
>> > Home network Setup: i have a comcast router\ filewall which bring in
>> > comcast internet connection. From the comcast the cable to my lingo ( voice
>> > over ip) router. From the lingo router it then goes to my Computer.
>> >
>> > Comcast router gives out IP in the range : 10.1.10.**
>> > Lingo router in the range : 172.125.25.**
>> > My machine is configured to obtain an IP and DNS automatically from the
>> > lingo router and it gives it 172.25.25.2 all the time.
>> >
>> > I configured my comcast and lingo router to pass on the Remote desktop
>> > request comming from the public IP to my machine and it works great. But
>> > the
>> > problem is that after i Remote desktop into my machine from outsite the
>> > network, if i connect to the VPN of my office network then remote destop
>> > bombs out and i cannot connect to my mahcine from outsite any more. After
>> > the
>> > VPN is connected when i do an ipconfig of my machine, my machine now has
>> > two
>> > IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the
>> > other
>> > IP 192.168.168.* that my office DNS server assigns and i think this is
>> > where
>> > my comcast and lingo routers get confused and not connect request comming
>> > for
>> > remotedesktop to my machine.
>> >
>> > so the question is how can i configure my comcast\ lingo router or my
>> > machine so that even when my home machine is connected over VPN to my
>> > office
>> > network i can Remote dektop into it.
>> >
>> > waiting for an answer.
>> >
>> > thanks
>> > sameer
>> >
>> >
>> >
>> >
>> >
>>
>>
>>

This sounds like you are connecting using a PPTP/L2TP connection.
My simple question. while you are connected to the office thru
the "VPN connection", can you browse internet? I believe you can't.

I am not quite sure what kind of firewall you are using at the office tho,
you need to use alternate method to establish a VPN connection to
your office. you need to find out what kind of firewall you are using at
your work.
ask your network guy at the office.

If you can use, for instance, IPSec instead of PPTP/L2TP, you should be
able to RDP to your home PC & to establish a VPN connection to your office
at the same time.

Hope it helps.

Takeshi



"sameer" <(E-Mail Removed)> wrote in message
news:7605A884-95E9-44FD-B8D6-(E-Mail Removed)...
> Hi Guys,
>
> My knowledge about networking is very basic since i am a software guy and
> my
> question is VPN related, when i am remote desktoped into my home machine
> from
> outsite the network and then onnect VPN to my office network, i am kicked
> out
> of remote desktop connect and can not connect back to the machine over
> remote
> desktop as long as the VPN is running, if i disconnect the VPN and connect
> again, i am in. Here are the details:
>
> Home machine : Windows XP Pro.
> LAN TCP\ IP properties : Optain an IP automitically, Obtain a DNS
> automatically.
> Home network Setup: i have a comcast router\ filewall which bring in
> comcast internet connection. From the comcast the cable to my lingo (
> voice
> over ip) router. From the lingo router it then goes to my Computer.
>
> Comcast router gives out IP in the range : 10.1.10.**
> Lingo router in the range : 172.125.25.**
> My machine is configured to obtain an IP and DNS automatically from the
> lingo router and it gives it 172.25.25.2 all the time.
>
> I configured my comcast and lingo router to pass on the Remote desktop
> request comming from the public IP to my machine and it works great. But
> the
> problem is that after i Remote desktop into my machine from outsite the
> network, if i connect to the VPN of my office network then remote destop
> bombs out and i cannot connect to my mahcine from outsite any more. After
> the
> VPN is connected when i do an ipconfig of my machine, my machine now has
> two
> IP addresses one that the lingo router assigsn i.e 172.25.25.2 and the
> other
> IP 192.168.168.* that my office DNS server assigns and i think this is
> where
> my comcast and lingo routers get confused and not connect request comming
> for
> remotedesktop to my machine.
>
> so the question is how can i configure my comcast\ lingo router or my
> machine so that even when my home machine is connected over VPN to my
> office
> network i can Remote dektop into it.
>
> waiting for an answer.
>
> thanks
> sameer
>
>
>
>
>