PDA

View Full Version : Official Network Troubleshooting Thread


Simmy
07-29-2008, 08:38 PM
Lo all,

I'm hoping we can make a thread about troubleshooting networks (both wireless and wired) and sticky it to the top of this forum section. I'll make a start later on as I've just got back from the gym and I'm too tired to do it now (Plus big brother is on :p).

If you've got any input yourselves, please add to this thread. I will try and edit the thread so that all the important info is well laid out in the first post.

acs
07-29-2008, 09:16 PM
My first step is always.
run
Cmd
ipconfig /all

That gives you plenty of info ( or none info) to start with.

jhoppe
08-06-2008, 11:37 PM
LEDs...making sure the LED's are lit and lit correctly...oftentimes, they get overlooked, but they are a good place to start.

Crgky127
08-07-2008, 03:11 AM
WinSockFix deserves a mention. Also on some laptops, there is a switch near the front to turn on/off the wireless radio. And even worse, some have a function key for it (it's worse because programs can turn it off without telling you for no reason!).

bmetman
08-30-2008, 11:51 AM
I think that is a great idea. That would definetly be a helpful thread. I like ipconfig/all, link lights and of course ping.

seedubya
08-30-2008, 05:47 PM
Depends on what the trouble is but the basics are....

cables secure,
link lights
ipconfig /all
ping localhost
ping 127.0.0.1
ping default gateway or other internal IP
ping www.google.com or other website, by name
ping 159.134.237.6 (or other external IP)

Somewhere in the midst of all this you'll hit a showstopper - start troubleshooting from there.

We need a troubleshooting flowchart to do this properly.

EDIT: I just signed up for Gliffy, an online flowchart creator. Login is NOSPAMMERScolmmwhelan@gmail.com PW is technibble
I have not started the diagram, I'll leave that to someone else.

minuswires
09-04-2008, 05:55 AM
I like to troubleshoot networks using the OSI MODEL.
Using all 8 Layers. Yes 8 layers. The "user" is the 8th Layer

Anywho start from the Cables/wires/ports then to the switching, etc.

Using the OSI Model really works for me. You don't miss any steps.

I also like to use Netstat -a
Netstat is a good way also to see if a machine has Spyware/Virus
because you get to see what connections are established.

In all my training I truly found Cisco's CCNA Course/Certification to be most helpfull in my career. It really takes you to the next level in understanding what really happens in the wire and client / server relationship.

TimeCode
09-04-2008, 06:11 AM
1) When installing a NetGear router NEVER use the CD that comes in the box. Turn it over, and look for the IP Address on the bottom. Set your PC's IP to the same subnet and then go to your browser and type in the exact IP Address that was on the bottom of the router. Set it up within the web interface.

2) Always have a cable tester to check that the pin-out is correct and there are no shorts.

3) ping 4.2.2.2

4) Don't bother pinging microsoft.com. It doesn't reply. Google and Yahoo do.

Wheelie
09-11-2008, 05:44 PM
I like to troubleshoot networks using the OSI MODEL.
Using all 8 Layers. Yes 8 layers. The "user" is the 8th Layer

Anywho start from the Cables/wires/ports then to the switching, etc.

Using the OSI Model really works for me. You don't miss any steps.

I also like to use Netstat -a
Netstat is a good way also to see if a machine has Spyware/Virus
because you get to see what connections are established.

In all my training I truly found Cisco's CCNA Course/Certification to be most helpfull in my career. It really takes you to the next level in understanding what really happens in the wire and client / server relationship.
Damn good info. Thanks.

lward1
04-29-2010, 12:51 AM
Well it has beem almost 2 years since I have had any real computer work, to many conflicts with my day job.

Any ways I have not realy stayed up to date on to much stuff and I had a neighbor ask to take a look at his problem. 1 desktop connected to router with cat.5, 2 laptops connected wirelessly. desktop and 1 laptop can be on the internet at time, if the 2nd laptop goes on line it will not connect and the other 2 drop the connection. Have to reboot modem and router to get the desktop back online. This happens with either laptop being on line first.

Dhcp Enabled and Autoconfiguration Enabled there is no encryption as they live on about 5 acres and have no close neighbors.

What the heck am I missing? It is probabbly so obvious I'm overlooking.
Thanks in advance.

Wheelie
04-29-2010, 01:43 AM
I have seen this issue go both ways.

1) where the wireless adapter on the "problem laptop" desperately needs a driver update to make it work correctly.

2) where the router does not like the wireless adapter on the "problem laptop" for some reason yet any other router has no issue with it.

Your gonna need to first try updating the WLAN driver on the laptop. In fact, I would update the WLAN and Ethernet drivers on all PC's in the home as a first course of action. If that not work then you'll need to try another router.

lward1
04-29-2010, 01:56 AM
Thanks for the input Wheelie, I'll try that tomorrow. maybe some of this will come back to me soon.

Update:
I have not been able to physically look at this issue yet, very busy at my full time job.
PC- Win XP Pro
Laptop1 - Win 7
Laptop2 - Win 7
Linksys WRT110 Router

I will check the drivers when I get there. I just don't understand how they can connect individually but when you try and get more than one on line the whole thing goes bonkers.

Like I said it has been several years since I was able to do this full time and dedicate time to keeping up to date with stuff like this, I'm sure it is something simple.

Thanks again.