Connection problems from inside LAN

Hi. I've got a server on my home computer (Subversion in this case -
but what server/port it is doesn't matter for this problem). My home
network just consists of an ADSL router, my computer, and my laptop.

I can connect to the server remotely no problem. If I try and connect
to the server from within the network (from either the laptop or the
computer which is running the server software), then I get ...

"No connection could be made because the target machine actively
refused it."

I can connect to the server from my main machine okay if I replace the
ip address with "localhost".

I've tried checking my logs on my router - and it's not reporting
anything going in or out of the LAN.
I've tried disabling all firewalls on my computer.
Nothing makes a difference.

Any ideas what's happening?

Cheers for any info,
- Dan

Re: Connection problems from inside LAN

On May 16, 4:27 pm, Dan wrote:
> Hi. I've got a server on my home computer (Subversion in this case -
> but what server/port it is doesn't matter for this problem). My home
> network just consists of an ADSL router, my computer, and my laptop.
>
> I can connect to the server remotely no problem. If I try and connect
> to the server from within the network (from either the laptop or the
> computer which is running the server software), then I get ...
>
> "No connection could be made because the target machine actively
> refused it."
>
> I can connect to the server from my main machine okay if I replace the
> ip address with "localhost".
>
> I've tried checking my logs on my router - and it's not reporting
> anything going in or out of the LAN.
> I've tried disabling all firewalls on my computer.
> Nothing makes a difference.
>
> Any ideas what's happening?
>
> Cheers for any info,
> - Dan

sounds like a DNS issue to me...

RedForeman

Re: Connection problems from inside LAN

On 17 May, 21:44, RedForeman wrote:
> On May 16, 4:27 pm, Dan wrote:
>
>
>
> > Hi. I've got a server on my home computer (Subversion in this case -
> > but what server/port it is doesn't matter for this problem). My home
> > network just consists of an ADSL router, my computer, and my laptop.
>
> > I can connect to the server remotely no problem. If I try and connect
> > to the server from within the network (from either the laptop or the
> > computer which is running the server software), then I get ...
>
> > "No connection could be made because the target machine actively
> > refused it."
>
> > I can connect to the server from my main machine okay if I replace the
> > ip address with "localhost".
>
> > I've tried checking my logs on my router - and it's not reporting
> > anything going in or out of the LAN.
> > I've tried disabling all firewalls on my computer.
> > Nothing makes a difference.
>
> > Any ideas what's happening?
>
> > Cheers for any info,
> > - Dan
>
> sounds like a DNS issue to me...


Are there any tests I can do to see if it is a DNS issue? Or any
ideas on what I can try to fix it?

Thanks again,
- Dan

Re: Connection problems from inside LAN

On May 22, 4:15 am, Dan wrote:
> On 17 May, 21:44, RedForeman wrote:
>
>
>
>
>
> > On May 16, 4:27 pm, Dan wrote:
>
> > > Hi. I've got a server on my home computer (Subversion in this case -
> > > but what server/port it is doesn't matter for this problem). My home
> > > network just consists of an ADSL router, my computer, and my laptop.
>
> > > I can connect to the server remotely no problem. If I try and connect
> > > to the server from within the network (from either the laptop or the
> > > computer which is running the server software), then I get ...
>
> > > "No connection could be made because the target machine actively
> > > refused it."
>
> > > I can connect to the server from my main machine okay if I replace the
> > > ip address with "localhost".
>
> > > I've tried checking my logs on my router - and it's not reporting
> > > anything going in or out of the LAN.
> > > I've tried disabling all firewalls on my computer.
> > > Nothing makes a difference.
>
> > > Any ideas what's happening?
>
> > > Cheers for any info,
> > > - Dan
>
> > sounds like a DNS issue to me...
>
> Are there any tests I can do to see if it is a DNS issue? Or any
> ideas on what I can try to fix it?
>
> Thanks again,
> - Dan- Hide quoted text -
>
> - Show quoted text -

Well... not really tests, just document your settings and keep them
consistent...

if your DSL modem is doing DHCP, then leave it to do that....

typical settings
DSL Router Settings
WAN IP XXX.XXX.XXX.XXX
LAN IP 192.168.1.1
DHCP pool of 192.168.1.10-25
DNS - point to external DNS of ISP(call ISP and ask what DNS addresses
they use.)

Internal PCs should have IPs of 192.168.1.10-25, subnet 255.255.255.0,
gateway 192.168.1.1, DNS could be either your 192.168.1.1, or your
external DNS provided by your ISP.... Most Routers will have 2
entries for DNS... both should be external. Your internal clients
should use 1, the routers internal address(192.168.1.1) and 2, the
external address provided by your ISP....

RedForeman

Re: Connection problems from inside LAN

On 22 May 2007 01:15:13 -0700, Dan wrote:

> Are there any tests I can do to see if it is a DNS issue?

To prove it is a DNS issue, you first test connectivity by using the
ip address in place of the name. If you connect using ip address
and fail using the correct name, you know you have a DNS issue.

Of course it is a bit hard getting ip address when DNS is dead.
You might want to get some ip address for testing before you have a
dns outage.

It is also handy to have a third party to look up an ip address. Say
http://samspade.org/ http://www.webyield.net/domainquery.html
http://www.geektools.com/whois.php

Linux stores DNS resolver ip addresses in /etc/resolv.conf
Your ISP provides those addresses as part of a DHCP lease.

If you like you could add a third entry of a free Public DNS ip to
your list of DNS servers which gives you a fallback if the ISP's
servers fail.

Downside of keeping a hardcopy of ip addresses, is they might change.
You can solve that problem by having a batch/cron job check them and
mail you a message when it sees a change.

No knowledge of scripting language.
http://tldp.org/LDP/abs/html/index.html

Re: Connection problems from inside LAN

> To prove it is a DNS issue, you first test connectivity by using the
> ip address in place of the name. If you connect using ip address
> and fail using the correct name, you know you have a DNS issue.


Using the IP address, I get exactly the same error. Does this mean
that it's not a DNS issue? If not, any other ideas?

Re: Connection problems from inside LAN

> Using the IP address, I get exactly the same error. Does this mean
> that it's not a DNS issue? If not, any other ideas?


Which IP address do you use?

PLease give a bit more description of your network.

Does the server have an internal address, which is different from the
external? If yes and you try to use the external address from within the
local network, that may not work, depending on the router you use.

Cheers,
Jens

Re: Connection problems from inside LAN

On 25 May, 18:47, Jens Hoffmann wrote:
> > Using the IP address, I get exactly the same error. Does this mean
> > that it's not a DNS issue? If not, any other ideas?
>
> Which IP address do you use?
>
> PLease give a bit more description of your network.
>
> Does the server have an internal address, which is different from the
> external? If yes and you try to use the external address from within the
> local network, that may not work, depending on the router you use.
>
> Cheers,
> Jens




I used the router's external IP address. On my laptop, I need to use
the external ip because I could be using it on the LAN - but I could
also be using it remotely too.

My router has an external ip and an internal ip. The internal ip is
192.168.0.1. It also has DHCP enabled.
My main computer (which is the server), has an ip of 192.168.0.2.
This is static, as I have ports mapped going externally to this
computer - so I don't want the IP to change. The router's DHCP range
goes from 192.168.0.3 to 192.168.0.99.
My laptop uses DHCP - but is normally 192.168.0.3.

> Does the server have an internal address, which is different from the
> external? If yes and you try to use the external address from within the
> local network, that may not work, depending on the router you use.

This may be the problem then. Do you know why this won't work? And
if there's any workarounds?

Re: Connection problems from inside LAN

Hi,

> This may be the problem then. Do you know why this won't work? And
> if there's any workarounds?

Most Routers do not like to send a packet back the same way they
received it. Usually this situation hints at loops, which are not very
healthy in most situations.

In the local network simply use the local address. If you want to use a
name (careful, confusion ahead!) then try to tinker with the name
resolution. Split DNS comes to mind (careful, confusion ahead).

You might succeed with entries in the local host file, but (did I tell
you about confusion?) if you move your laptop to the outside, you will
have to manually change the entries.

Cheers,
Jens