Computer questions

[bsercombe]

Yeah, any piece of kit that you can borrow and test will help- first law of IT support is check the cables too!

[Mean Machine]

The cables are fine, i've tried a few different cables and the same thing happens with all of them. I'll try and find a modem to borrow and test that, cheers.

[Mean Machine]

This just gets better and better. *hates hogging thread*

So I tried another modem, it worked fine, plugged in my old one and now it's working fine too. The problem is no longer occurring for some reason (it would have happened again by now). BUT now the other computer that's connected to the internet through my router won't connect to the net. It's connected to the network, but not the internet. I've tried the usual things and nothing seems to change it but like I said before, i'm a n00b at networking.
The cable isn't the problem, I tested that. And i'm pretty sure it's not the router because it's connecting to a network through it, just not the internet.

So, if anybody can suggest anything I should try then it would be greatly appreciated. I don't like asking so many questions in this thread but I had a search around the net and couldn't find anything that helped. Perhaps if somebody could suggest any network setup steps I might have missed as i'm sure it's something basic i've missed/stuffed up haha.

[Rick]

Have you tried plugging them through a switch first?

[bsercombe]

Open a DOS prompt on the both computers (start/run/cmd [enter])
type ipconfig /all on both computers
On each computer you should see things like:

Ethernet adapter Local Area Connection:

IP Address. . . . . . . . . . . . : 10.0.120.17
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . : 10.0.220.10
DHCP Server . . . . . . . . . . . : 10.0.0.2
DNS Servers . . . . . . . . . . . : 10.0.0.2

If you feel really excited, post what both sets of those numbers are before you attempt the following (it might give me further information I can help you with prior to making a bigger mess by following the instructions below ) Read the whole of the below before doing anything...

There is other stuff, but this is the important stuff. The last number in the IP address (.17 in the example above) should be the only number that is different between the two machines. If most of the numbers are totally different then your computer is not getting an address from your router. Try typing:

ipconfig /release [enter]
ipconfig /renew [enter]

On the computer that is not working and post any error messages you get to me (like could not obtain an address from the DHCP server etc.). If you can see the local network OK but web browsing does not work then the problem will most likely lie with the DNS server or the default gateway.

Go into your network connections (Start/Connect TO/Show all connections on XP), right-click the local area connection select properties from the menu, select Internet Protocol (TCP/IP) from the window then click properties. Make sure that obtain IP address and Obtain DNS automatically are both selected and the windows to enter those numbers are greyed out. Click Ok if you made any changes cancel if you didn't.

Lets see where that gets you....


There is some info I don't have... there are three ways you can connect two machines to the internet:

1. Your ADSL Modem has ports to plug multiple computers into (the above procedure is valid)
2. You have another device (hub or wireless router) between your two computers (the above procedure is valid)
3. You plug your ADSL modem into one computer, connect the two computers together with a crossover cable and have enabled internet connection sharing on the computer plugged into the ADSL modem (DON'T use the above procedure you probably have static IP addresses in your computers and switching them over to obtain an address automatically will fail.)

[pipsqeek]

Originally Posted by bsercombe

Ethernet adapter Local Area Connection:

IP Address. . . . . . . . . . . . : 10.0.120.17
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . : 10.0.220.10
DHCP Server . . . . . . . . . . . : 10.0.0.2
DNS Servers . . . . . . . . . . . : 10.0.0.2

I think it should be:
IP Address. . . . . . . . . . . . : 10.0.120.17 <--- Class A IP Address
Subnet Mask . . . . . . . . . . . : 255.0.0.0 <--- Class A subnet
Default Gateway . . . . . . . . . : 10.0.220.10
DHCP Server . . . . . . . . . . . : 10.0.0.2
DNS Servers . . . . . . . . . . . : 10.0.0.2


Forgive me if I'm wrong. I just got home from a long session on the grog.
pipsqeek

[Mean Machine]

Before I try that, can I just ask whether the following setup would actually work (so I can double check that it's not the cables at fault)

Internet into modem
USB cable running internet to main PC and ethernet cable running into router (both from modem)
Then a second ethernet cable running from the router to the second computer.

So instead of running both PC's out of the router, i'm only running one out of the router and one straight through the modem. Is it possible to have both connected to the net that way?

[bsercombe]

Heads up Myspace visitors (and page owners). This is more likely to be done to high traffic pages but anyway...

The MySpace pages of several musicians, including the personal page of R&B songstress Alicia Keys, were targeted this week by hackers as part of a scheme to spread socially engineered attacks and render the computers of visitors to these pages vulnerable to future invasions, according to The New York Times.

While it was unclear at press time how the pages were compromised, experts warn that they're now very dangerous places to visit online. Among the attacks being served by Keys' page (and those of French funk band Greements of Fortune and Scottish rock band the Dykeenies) are Trojan horses disguised as new video codecs.

When someone tries to access one of the hacked sites, an exploit first attempts to install malware (malicious software) on the visitor's computer. If that doesn't work, the user is next asked to install a fake codec to view a video posted on the page, according to the Times. When installed, these malicious programs actually change the computer's Domain Name System settings to redirect future searches to unauthorized sites — including porn Web sites and URLs selling bogus security software — thus allowing hackers to take over what users see on their browsers and what they download onto their computers.

[bsercombe]

Originally Posted by Mean Machine

Before I try that, can I just ask whether the following setup would actually work (so I can double check that it's not the cables at fault)

Internet into modem
USB cable running internet to main PC and ethernet cable running into router (both from modem)
Then a second ethernet cable running from the router to the second computer.

So instead of running both PC's out of the router, i'm only running one out of the router and one straight through the modem. Is it possible to have both connected to the net that way?

If the ADSL modem doesn't have an ethernet port then that's the only way you can do it. If it does, you normally run the Ethernet from the ADSL modem to the Internet port (or WAN port) of your router then plug both computers in to other ports on your router.

The way you have set up, you would probably need to use static addressing on the computer not plugged in to your router and/or enable internet connection sharing on the computer plugged in to your ADSL modem.

[bsercombe]

Originally Posted by pipsqeek

I think it should be:
IP Address. . . . . . . . . . . . : 10.0.120.17 <--- Class A IP Address
Subnet Mask . . . . . . . . . . . : 255.0.0.0 <--- Class A subnet
Default Gateway . . . . . . . . . : 10.0.220.10
DHCP Server . . . . . . . . . . . : 10.0.0.2
DNS Servers . . . . . . . . . . . : 10.0.0.2

Forgive me if I'm wrong. I just got home from a long session on the grog.
pipsqeek

Hi Pips, you only need a class A subnet if you have a bazillion devices on the same ethernet segment. Most companies large don't do that, they segment their network using subnets or vlans. Too many packets even in a switched environment will lead to collisions and poor performance.

The netmask divides a range of IP addresses into subnets. So in Singapore when I am given a range of IPs from our ISP for our company to use, I get 203.125.24.209 with a netmask of 255.255.255.240 (14 IP addresses I can use which are "public" on the internet).

Our IP schema works like this:

10.Location.Function.Device

So I know all 10.1 machines are in Singapore, 10.2 are in Dubai 10.3 are in Houston etc. Giving me 256 locations (our company will never need more than that).

Then the Function- 220 is always router addresses, 11 -22 is servers, 120 -130 is DHCP etc.

Then you have the individual device. This way I'll be able to walk into a site I have never seen and find the machines I need very quickly. Also makes things easier for hackers

The company next door has 25 staff. Their netmask is 255.255.255.0 as they will probably never have more than 256 devices to worry about. 50 addresses are set aside for DHCP even though they only have 25 staff (you need to have a bit extra for visitors etc.). More than enough space!