Network nightmare

  • Thread starter Thread starter NT
  • Start date Start date
N

NT

Hi


There's one router, 3 computers, all being networked for the first
time. But...

Computer 1 works fine via router ports 1 or 2 (other ports not tried),
running linux mint 7 or win98

Computer 2 runs mint 6 and win98, but neither will connect to the
network. New NIC has been fitted, but still no joy. No error messages
given unfortunately.

Computer 3 runs XP, that won't connect either. XP error message says
the router wont assign it an IP address - but the router works fine
with computer 1.

Ugh... where do I start!

Thanks, NT
 
NT said:
Hi


There's one router, 3 computers, all being networked for the first
time. But...

Computer 1 works fine via router ports 1 or 2 (other ports not tried),
running linux mint 7 or win98

Computer 2 runs mint 6 and win98, but neither will connect to the
network. New NIC has been fitted, but still no joy. No error messages
given unfortunately.

Computer 3 runs XP, that won't connect either. XP error message says
the router wont assign it an IP address - but the router works fine
with computer 1.

Ugh... where do I start!

Thanks, NT
Click to expand...

On my router, on the DHCP setup, I can assign a starting address, plus
specify the maximum number of DHCP addresses the router will serve.

For example

192.168.100.23 and four addresses, would give

192.168.100.23
192.168.100.24
192.168.100.25
192.168.100.26

Check your router settings, to make sure the DHCP address pool is large
enough for the number of devices. If you set the router to only deliver
one address, then any subsequent attempt to get a DHCP address will fail.

Paul
 
On my router, on the DHCP setup, I can assign a starting address, plus
specify the maximum number of DHCP addresses the router will serve.

For example

    192.168.100.23  and four addresses, would give

    192.168.100.23
    192.168.100.24
    192.168.100.25
    192.168.100.26

Check your router settings, to make sure the DHCP address pool is large
enough for the number of devices. If you set the router to only deliver
one address, then any subsequent attempt to get a DHCP address will fail.

    Paul
Click to expand...

How do I check this? Its a cheap TP brand network switch and I wouldnt
know where to find settings, or if it even has them.


thanks, NT
 
NT said:
How do I check this? Its a cheap TP brand network switch and I wouldnt
know where to find settings, or if it even has them.


thanks, NT
Click to expand...
How are you connecting to the internet? Is it a cable or DSL modem? Either
one can be setup by the ISP vender to only allow one IP address.

It sounds like you have an internet interface device from your ISP, then a
cable over to the TP Switch.
The ISP is using the MAC address of the original PC that worked as your
source PC and is ignoring the other two. That can happen if your ISP wants
more money in order to provide you with more IP address numbers and you are
using what is known as a "dumb bridge" and not a true router to divide the
internet between the (now) three computers. With that kind of ISP you
either have to use a "real" router and not just a dumb switch or pay them to
provide more than one IP address. With most real routers you can use DHCP
spoofing to load the original working PC's MAC address into it, making the
ISP think the router is your old computer. The router then splits the
internet and assigns new IP address values to all three devices.

So give us more information to work with. What is the name/model of the
device that is actually hooked into your ISP. Same goes about the TP brand
box if it is different. The name of your ISP might help as well.
 
How do I check this? Its a cheap TP brand network switch and I wouldnt
know where to find settings, or if it even has them.


thanks, NT
Click to expand...

A switch is not a router. If all you're connecting to is a switch, it
won't provide any DHCP addresses.
 
NT wrote:

How are you connecting to the internet?  Is it a cable or DSL modem?  Either
one can be setup by the ISP vender to only allow one IP address.
Click to expand...

Its virgin cable, which provides a cat5 output
It sounds like you have an internet interface device from your ISP, then a
cable over to the TP Switch.
yes

The ISP is using the MAC address of the original PC that worked as your
source PC and is ignoring the other two.   That can happen if your ISP wants
more money in order to provide you with more IP address numbers and you are
using what is known as a "dumb bridge" and not a true router to divide the
internet between the (now) three computers.  With that kind of ISP you
either have to use a "real" router and not just a dumb switch or pay themto
provide more than one IP address.  With most real routers you can use DHCP
spoofing to load the original working PC's MAC address into it, making the
ISP think the router is your old computer.  The router then splits the
internet and assigns new IP address values to all three devices.
Click to expand...
So give us more information to work with.   What is the name/model of the
device that is actually hooked into your ISP.  Same goes about the TP brand
box if it is different.  The name of your ISP might help as well.
Click to expand...

ok, that's all in another post below now.


Thank you, NT
 
Do a netstat /all on mint or ipconfig /all in windows and see what ip
address is assigned each computer. Make sure DHCP is on on the router.
If you use mac filtering make sure the macs are in the router.
Click to expand...

OK, Mint 6, which doesnt conect and said 'network disconnected' after
boot, reports many pages of response to netstat /all. 3 lines of
unix 2 DGRAM ...
and loads of
unix 3 STREAM CONNECTED...
.... I've really no idea what I'm looking for here.

Win98, which connects fine, runs the dos util but the dos box closes
in a fraction of a second, nothing can be read.

Redirecting the text to a log file under either system is an issue at
the moment. If mint did record it, I cant find it anywhere. Windows
failed to create the text file, despite several attempts using >.

Computers, don't you love em.


NT
 
The network switch:
http://www.tp-link.com/products/product_des.asp?id=80
Click to expand...

8-port Unmanaged 10/100M Desktop Switch
The virgin cable box is an Ambit E08CO13.00
Click to expand...

It would be a lot easier to establish a network with a router/NAT device
than that 8 port switch.

Cisco/Linksys (over)simplifies the comparison of switches and routers by
saying "The router is the central component in connecting all of your
computers and network devices together, allowing them to access and
share one high-speed Internet connection. ... A router combines the
functions of a switch, which organizes and controls data flow among your
computers and network devices. A switch is best for sharing files and
printers within wired networks. A switch does not provide Internet
access." http://snipr.com/s3efj How Routers Work

If you had a router/NAT device, then each of the computers could get an
IP address from the router which gets its (single) IP address and
internet connectivity from the cable box.

The cable box only wants to give out one IP address to 'something'. The
router becomes the something. The computers get their IP addresses from
the router giving them a translated local network address.
 
Mike said:
8-port Unmanaged 10/100M Desktop Switch
Click to expand...

I neglected to look up the cable box which is a Ubee found here:

http://snipr.com/s3f1g Euro DOCSIS 2.0 Data Cable Modem - E08C013
It would be a lot easier to establish a network with a router/NAT device
than that 8 port switch.
Click to expand...
The cable box only wants to give out one IP address to 'something'.
Click to expand...

Your cable box will do more than that.

<ubee/ambit> In addition to allowing PCs to share an Internet
connection, the Cable Router supports high-end features including IPSec
VPN, SPI Firewall, Access Control Lists, Static Routing, and much more.
.... </ubee/ambit>

The diagram in the support .pdf shows 3 computers ethernet wired to a
'hub' (which can be a switch) which is ethernet wired to the cable modem
which also has another computer USB/d to it. The modem only has one
ethernet port and one USB and the cable.

I'm not clear on how to use this modem with multiple computers. There
is only a 'data sheet' with spec information, no manual at the ubee
link.
 
I neglected to look up the cable box which is a Ubee found here:

http://snipr.com/s3f1g Euro DOCSIS 2.0 Data Cable Modem - E08C013




Your cable box will do more than that.
Click to expand...


Perhaps virgin dont want it to do more than that? I get the feeling
the simplest thing to try would be a real router. Think what I'll do
is connect each machine singly to the cable box, without the TP switch
in the way, should tell me something.


thanks for all your help, NT
 
NT said:
Win98, which connects fine, runs the dos util but the dos box closes
in a fraction of a second, nothing can be read.
Click to expand...

I suspect that the reason the DOS box is closing so quickly is that you
are running IPConfig from the start/Run box... The DOS box is closing
after running the utility.

Open the DOS box, then type "ipconfig /all" in it... The output will
appear and the window will stay open.

Rarius
 
I suspect that the reason the DOS box is closing so quickly is that you
are running IPConfig from the start/Run box... The DOS box is closing
after running the utility.

Open the DOS box, then type "ipconfig /all" in it... The output will
appear and the window will stay open.

Rarius
Click to expand...

Thank you.

Ok... the pc that connects, under win98:
(some numbers xxed out)

Windows 98 IP Configuration Host Name . . . . . . . . . : 500 DNS
Servers . . . . . . . . : 194.xxx.4.100
194.xxx.8.100 Node Type . . . . . . . . . : Broadcast NetBIOS Scope
ID. . . . . . : IP Routing Enabled. . . . . : No WINS Proxy
Enabled. . . . . : No NetBIOS Resolution Uses DNS : No 0 Ethernet
adapter : Description . . . . . . . . : PPP Adapter. Physical
Address. . . . . . : 44-xx-53-54-00-00 DHCP Enabled. . . . . . . . :
Yes IP Address. . . . . . . . . : 0.0.0.0 Subnet
Mask . . . . . . . . : 0.0.0.0 Default Gateway . . . . . . : DHCP
Server . . . . . . . . : 255.255.255.255 Primary WINS
Server . . . . : Secondary WINS Server . . . : Lease
Obtained. . . . . . . : Lease Expires . . . . . . . : 1 Ethernet
adapter : Description . . . . . . . . : Kingston EtherRx PCI 10/100
Fast Ethernet Adapter (KNE110TX) Physical Address. . . . . . : 00-C0-
xx-58-74-58 DHCP Enabled. . . . . . . . : Yes IP
Address. . . . . . . . . : 82.xx.207.100 Subnet
Mask . . . . . . . . : 255.255.252.0 Default Gateway . . . . . . :
82.xx.204.1 DHCP Server . . . . . . . . : 62.xxx.131.74 Primary WINS
Server . . . . : Secondary WINS Server . . . : Lease
Obtained. . . . . . . : 09 24 09 19:26:16 Lease
Expires . . . . . . . : 10 01 09 19:26:16


And the pc that wont connect, again under w98:

Windows 98 IP Configuration Host Name . . . . . . . . . : 2PT4 DNS
Servers . . . . . . . . : Node Type . . . . . . . . . : Broadcast
NetBIOS Scope ID. . . . . . : IP Routing Enabled. . . . . : No WINS
Proxy Enabled. . . . . : No NetBIOS Resolution Uses DNS : No 0
Ethernet adapter : Description . . . . . . . . : PPP Adapter.
Physical Address. . . . . . : 44-xx-53-54-00-00 DHCP
Enabled. . . . . . . . : Yes IP Address. . . . . . . . . : 0.0.0.0
Subnet Mask . . . . . . . . : 0.0.0.0 Default Gateway . . . . . . :
DHCP Server . . . . . . . . : 255.255.255.255 Primary WINS
Server . . . . : Secondary WINS Server . . . : Lease
Obtained. . . . . . . : Lease Expires . . . . . . . : 1 Ethernet
adapter : Description . . . . . . . . : PPP Adapter. Physical
Address. . . . . . : 44-xx-53-54-00-01 DHCP Enabled. . . . . . . . :
Yes IP Address. . . . . . . . . : 0.0.0.0 Subnet
Mask . . . . . . . . : 0.0.0.0 Default Gateway . . . . . . : DHCP
Server . . . . . . . . : 255.255.255.255 Primary WINS
Server . . . . : Secondary WINS Server . . . : Lease
Obtained. . . . . . . : Lease Expires . . . . . . . : 2 Ethernet
adapter : Description . . . . . . . . : VIA PCI 10/100Mb Fast
Ethernet Adapter Physical Address. . . . . . :
00-0C-xx-53-F8-7D DHCP Enabled. . . . . . . . : Yes IP
Address. . . . . . . . . : 169.xxx.131.187 Subnet
Mask . . . . . . . . : 255.255.0.0 Default Gateway . . . . . . :
DHCP Server . . . . . . . . : 255.255.255.255 Primary WINS
Server . . . . : Secondary WINS Server . . . : Lease
Obtained. . . . . . . : 09 25 09 9:39:17 PM Lease
Expires . . . . . . . :


thanks,
NT
 
NT said:
Perhaps virgin dont want it to do more than that? I get the feeling
the simplest thing to try would be a real router. Think what I'll do
is connect each machine singly to the cable box, without the TP switch
in the way, should tell me something.


thanks for all your help, NT
Click to expand...

On many providers testing in the following order may be of assistance in
identifying what an ISP has setup.

1. Power down the ISP's box and all computers being tested.
2. Power on only the ISP's box and wait for it to stabilize.
3. Plug one PC directly to the ISP's box using a standard eithernet cable
and power on the PC.
4. If this PC comes up and works on the internet go back to step #1 and try
the list on the next PC You do need to power down the ISP's box between
each test as many of them store the setting of the first PC it allows to
pass through it. If all PC's are able to work individually with the above
procedure then any router (not just a switch) will take care of your PC's
sharing the internet

If each PC is set for DHCP and can individually work on the internet using
the above procedure but not when connected through a switch then the problem
is an ISP that has set their box to only supply one IP address. You may be
able to modify the settings in the ISP's box to supply more IP's or ask them
to (usually at a higher monthly cost) but it is usually much easier to
purchase a cheap 4 port router or even one that includes a wireless
connection, for future use if nothing else. You could get by with a single
port router and use the switch you have to split things as the router can be
set to supply more than one IP address even though it only has one Ethernet
port but the cost difference between a one port and a four port one is
usually minimal

A few of the real anal ISP's keep track of the PC's MAC address and store it
at the host router making the above test fail on all but the actual PC that
connected with them during your initial account setup. For those you would
need a router that includes the ability to change or "spoof" the MAC address
of the router to match the router.

The other thing that can make the above test fail is if your computer is
actually sending the PPP authorization, such as a username and password to
the ISP. Usually initially configured by using their software for those who
don't know any better. That too can be taken care of by using a router that
can be set to send the PPP values in place of the PC.

Good luck.
 
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