How to Solve Wirelesss router issues vs. ISP issues

Question

So I've been having a lot of issues with my internet connection since installing 12.04. This is happening on both of my laptops that run this version. My mac has no issues although I did just notice one page that took a while to load. Which brings me to the question. What tools should I get and how would I go about testing whether the issue is at the wireless or the actual internet. Is there something that could monitor and tell me if there are lapses in connection? This whole time I've been assuming that my older laptop (2005) and my netbook are just not getting along with Ubuntu 12.04 but it would be nice to be able to actually test this rather than just assume...even though the mac is good 99% of the time... Maybe the router is conflicting with Ubuntu? Maybe the internet goes in and out? Who knows... Thanks!

Answer 1

The easiest way to tell if it's your wireless network\your laptop wireless interface or if it's your Internet connection is going to be the ping utility.

Here's what you need to do

1. Find the IP of the default gateway on your network:

   -Open up a terminal and type:

   ip route show
   

   Here you're looking for an entry that looks like this:

   default via 192.168.1.1 dev wlan0  proto static
   

   The "192.168.1.1" part is the IP of your default gateway (AKA your router). Obviously your IP may differ.

2. Ping the IP of your gateway:

   -Back in the terminal type:

   "ping" then the IP of your gateway. For instance if your gateway IP was 192.168.1.1 you would type:

   ping 192.168.1.1
   

   The ping command simply sends an echo request and if everything is working right you should begin to see responses from the gateway that look like this:

   64 bytes from 192.168.1.1: icmp_req=3 ttl=64 time=1.35 ms
   

   Or you might see something like this which indicates dropped packets:

   From 192.168.1.113 icmp_seq=1 Destination Host Unreachable
   

   Let that run for a minute or so to get a good sample size. You should see replies continue to scroll down the terminal until you hit CTRL + C to stop the ping.

3. Now we ping a random host on the Internet for comparison:

   -Open up a second terminal (File->Open Terminal) and follow the same procedure, this time using the command:

   ping www.google.com
   

4. Now you have two samples that we need to compare:

   -Scroll through the replies in the first sample and look for dropped packets (see above) or very high latency (over 100ms in the "time" field).

   If if you see a lot either of these issues in the first (default gateway) sample, you can reasonably assume that there's an issue either with your wireless network (or router) or with your laptop/wifi harware.

   If the first sample looks fine but you see a bunch of issues with the second (Internet sample) then it reasonable to assume that the issue is with your connection to the Internet.

Take several samples for longer lengths of time if you need to, that will only give you a better idea of what's going on.

If you think the issue might be with your laptop you should try from another computer and see if you get the same or different results.

Good Luck!