Examining PING results..anyone?

[molecul3]

Hi all,

I am having this frequent problem at my office. Today, when everyone in my office tries to access a site (e.g.

http://www.thesitename.com)

it won't work. When i try to access that same site without "

http://www",

it won't work either. But sometimes, i try to access that site with "www" it works and without "www" it doesn't. Note that I am talking about the same URL in all cases.

What could be causing this?? When i try to ping that site with "www" 1 or 2 out of 4 pings will time out but when i run ping again without "

http://www",

i will get successful replies on all attempts. I repeated this a few times and got the same results. When i return to my office tomorrow, everything works fine again, with and without the "www" i am able to access that site. This problem occurs occassionally and i would REALLY like to know what is the problem or how do i go about finding out what is causing the problem. Thanks everyone. Hope someone can help me out.

Regards,
George

 

[RussellMcL]

Is this with one specific site or with all sites?

 

[MrBurritoMan]

what would help us out the most is for you to copy/paste the command window and in particular your ping command and results. to do this:

start with the command window open and right click in the middle of it.

then select mark.

now with the mouse drag and make a box around all the stuff that you want to copy.

let go of the left mouse button and then press enter.

your command window is now stored in your clip board.

just paste it here and we shall see what we can do.
-MrBurritoMan

 

[cgkeller]

I am sorry smyap3, if I am budding in in your question "Examining PING results". I just would like to compliment Mr.BurritoMan for his article about Win-DOS-Box.

I tried it and you know what I found out?
If you click on "Select all" instead of "Mark", it will convert your text from white to black and your background color will change to white, which is exactly what I wanted to do for the longest time.

Because if you print your Win-DOX-Box with a black background, it looks horrible!

Thank you for your valuable tip.

Charles.

 

[wybnormal]

Lets keep the basics in play here.

When you can not use the

http://www prefix,

you have lost the name resolution for some reason. Are you using internal or external DNS servers? Can you ping using the IP address of the target? If you can ping using the IP, then it's a DNS issue. If you an not ping the IP, then it's a connectivity issue.

When troubleshooting, traceroute is almost always a more useful command to use for a varity of reasons. One is more information is given back to you as the user. A technical reason is that unlike ping which is purely ICMP, traceroute using UDP on the outbound side and ICMP to return the "error" message. This gets around some possible firewall restrictions of not allowing ping to pass the firewall.

Anyways, are your network configs pushed using DHCP or are they static?

MikeS

http://www.packetattack.com

http://www.packetpress.net

Home of the book "Network Security Using Linux"

 

[molecul3]

Hi MikeS,

All the office tenants in the building are assigned a static IP for their router. This static IP is assigned on a server which is the gateway for all tenants. This gateway then uses DNS servers of the ISP. Does that make sense? However, within each unit itself, all machines are assigned IP automatically by the router.

So, for each tenant...the config of the router will be something like this...

for WAN...

IP: 192.168.0.20
S/Mask: 255.255.255.0
DNS: 192.168.0.1 (which is the gateway or the server in the building)

for LAN...

auto DHCP

I have realized then when we are experiencing the same problem as i stated in my first post, trace route provides dissimilar results when i trace route with the

http://www and

without the www. For example, running trace route with

http://www may

not time out in any nodes whilst running it without

http://www will

cause time outs in several nodes. For your info, i can ping with the IP as well as host name.