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How to Use Traceroute

Traceroute is an application that traces the path data takes from one computer to another. Basically a??traceroute is a map that shows what stops or locations that data must pass through in order to go from one computer to another.

To be effective troubleshooting tool, the?traceroute needs to be run during a time when ?the problem is occurring, from a computer that is experiencing the problem.

How do I run a traceroute?

To Run a Traceroute in Windows:

In Windows 98 or ME, Go to Star? > Run. Type command? and press the Enter? key.
In Windows 2000, XP, or Vista, go to Start > Run and type cmd? and press the Enter? key.

This will bring up a black command prompt window. It will have a line that looks like this:

C:\Documents and Settings\>

with a cursor blinking next to the >? symbol.

To run the traceroute, type:
tracert yourdomain.com

Where yourdomain.com? is the name of the server that you are having difficulty connecting to. The?traceroute process may take only a few seconds or a few minutes. Typically, the farther you are away, geographically, from your target location, the longer the trace will take.

If you have difficulty copying the traceroute information, or if it runs off the screen, you can instead type:

tracert yourdomain.name > C:\trace.txt

This would write the command results to a text file named trace.txt in the root of your C: drive.

To Run a Traceroute on a Mac:

If you have OS X, you can use the built-in network tools. Double-click the Hard Drive icon > Applications folder > Utilities folder > Network Utility program. Select the Traceroute tab and enter the hostname or domain name.

Mac OS X users can also take advantage of the the terminal that is built in to the system. Inside the same Utilities folder described above and open the program labeled Terminal. Once inside the terminal application type in the command ‘traceroute domain.com’. Be sure to leave out the quotation marks and substitute the target server name or IP address instead of domain.com

If you have an older Macintosh, you may need to acquire third party software utility software. Go to http://www.tucows.com and do a search for Trace? on Macintosh?. Programs like the DNS Expert Professional will allow you to run a trace route?. Then send us the results for analysis.

To Run a Traceroute on Linux or UNIX:

At the command line, type:
traceroute yourdomain.com
FOR All SYSTEMS:
Please note that yourdomain.com should be replaced with the site is not working for you.

WHAT DOES THE TRACEROUTE SHOW YOU?

Let’s take a few sample traceroute outputs. The first is a successful trace:
Tracing route to xeonbd.com [67.43.13.136]
over a maximum of 30 hops:

1 1 ms 1 ms 1 ms 10.18.61.1
2 1 ms 1 ms 2 ms 116.193.170.161
3 4 ms 3 ms 1 ms 116.193.169.245
4 5 ms 4 ms 7 ms bgp1.ispros.com.bd [116.193.170.1]
5 3 ms 11 ms 10 ms 123.49.4.41
6 3 ms 2 ms 7 ms 123.49.13.94
7 150 ms 153 ms 150 ms pal9-bangladesh-4.pal.seabone.net [213.144.181.125]
8 195 ms 205 ms 193 ms decix-fra52-racc2.fra.seabone.net [195.22.211.107]
9 187 ms 205 ms 217 ms global-crossing-2-decix.fra.seabone.net [89.221.34.50]
10 324 ms 329 ms 322 ms 64.209.88.186
11 314 ms 305 ms 304 ms lw-dc2-core3-te9-1.rtr.xeonbd.com [209.59.157.224]
12 310 ms 310 ms 313 ms lw-dc2-sec3-dist5-sec3-po1.rtr.xeonbd.com [209.59.157.118]
13 313 ms 310 ms 310 ms 67.43.13.136

It looks like gibberish, right? But it actually fairly easy to understand. After the traceroute command, the program tells you what it doing;

It looked up the domain xeonbd.com,
It found xeonbd.com on the IP address of 67.43.13.136
Now it will now attempt to find its way there.

It will only be able to attempt 30 hops (stops along the way, or connections to routers) and it will send a packet of 40 bytes.

The numbers at the far left are the number of the hop, followed by the name and/or IP address of the router that hop is going through. You can see our trace started within the XeonBD network, progressed through AT&T and found its way to msu.edu.

The set of three numbers on the right side of the lines indicate the amount of time, in milliseconds, it took for that hop to complete. Traceroute performs each hop three times.

In this example there are no asterisks (which indicate packet loss) and no inordinately long delays. If your trace to the server looks like this, you are in good shape in terms of network connectivity.

Now, lets look at a traceroute that ends without reaching its destination:
traceroute xeonbd.com
traceroute to xeonbd.com (209.59.139.21), 30 hops max, 40 byte packets
1  lw-dc2-hsrp-vlan132.rtr.xeonbd.com (67.43.8.129)  0.947 ms  1.028 ms  1.101 ms
2  lw-dc2-core4-po2.rtr.xeonbd.com (209.59.157.131)  1.275 ms  1.308 ms  1.385 ms
3  lw-dc1-core1-ge3-5.rtr.xeonbd.com (209.59.157.93)  1.849 ms  1.921 ms  1.980 ms
4  lw-dc1-dist1-ge1.rtr.xeonbd.com (209.59.157.2)  92.082 ms  92.155 ms  92.347 ms
5  * * *
6  * * *
7  * * *
8  * * *

[truncated]

Our trace to xeonbd.com failed because we ran it from our internal network xeonbd.com is not actually down. It’s just a nice, short example of what a failed trace looks like.

You can see on the fifth hop we have nothing but packet loss. The traceroute continued for the full 30 hops, each reporting * * * as it went. If your trace to the server has many asterisks like this one, that means that the connection was not able to be completed. ?This could be for a variety of reasons including:

A network outage
High amounts of traffic causing network congestion
A firewall dropping traffic from your IP

If you see these asterisks once you are inside XeonBD’s network, there may be no need to worry. VPS customers frequently are not able to trace to their instance on the parent server.

Having traceroute output ready is an excellent way to help us help you if you are experiencing network issues.

Posted in: DNS Propagation, Domain Name Server(DNS), Domain Registration, Open Page

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What is DNS propagation and why does it take so long?

So you found a perfect domain name that was not already taken, figured out how to register it, paid for hosting (leasing space to store all the files that will be publicly accessed as web pages) with a WHP – aka Web Hosting Provider (such as xeonbd.com) and even uploaded your website to the WHP servers, or had a professional design firm create a web site for you.

Also, it looks like the results of your hard work, of your money spending and of the headaches you got from trying to make sense of all the technobabble were in vain? Why can’t you see your website instantly – after all? Isn’t? This the promise of the e-commerce age? Hey, when they took your credit card payment, that went pretty fast!! Is it that nobody really cares about customer service anymore? And what is this “propagation” nonsense those techies are trying to bamboozle you with?

Is your new Web Host Provider a lemon? Did you make a big mistake choosing it?

All this has to be very frustrating, unless you understand exactly how things work. Over the next few paragraphs, I will try to?demystify?the DNS propagation process, by telling you in plain English, what DNS propagation is, how it works, and why is it that the only thing we can do to speed the process up is…. wait.

DNS stands for Domain Name Server. I know the word Server is intimidating and you are thinking “oh sure, another article written in?technical?language”. Think of a server as a regular computer, like the one you are using now to read this. That’s right! Your beloved computer can be a server too. We call a computer a server when that machine is up and running and providing a service (“serving” something, whether a web page, a text document, etc.)

With the language?barrier?lowered, I will tell you that DNS can be tricky, especially when first registering a domain name or transferring your website to a web hosting provider. The strangest things can happen that would lead you to believe that your new web hosting provider is at fault.

99.99% of the time the Web Hosting Provider is not to blame and I will explain why.

There are a number of things involved in DNS that I will familiarize you with. Sorry, but it has to be done. Again, like everything else in life, once you understand how things work, things will look much brighter.

Things you need to hear about are:

- IP Addresses

- Service Providers

- Domain Names

- Domain Name Registrars

- DNS

- The Propagation Process

1. IP Addresses

Our computers talk to each other by identifying themselves using numerical addresses much like the address on your home or for your telephone. When one computer wants to speak to another computer, it all boils down to an address or what we call an “IP Address”.

Here is an example: 64.247.43.26

As you would imagine, the number of possible addresses, while immense to the untrained eye, is actually limited and we are almost on the verge of exhausting all the numbers…. Here’s a piece of trivia for all interested in cool facts: Typically, service providers receive thousands of IP addresses to be used on their networks. IP addresses in the United States are assigned by ARIN, the American Registry for Internet Numbers. They are the assigned numbers authority and they control who gets IP addresses in the US.

2. Service Providers

The service providers will use IP addresses to identify their network equipment so that they can conduct business on the internet.

There are many different types of service providers but for the purpose of this article, I will only discuss two of them.

The ISP (or Internet Service Provider) is the company that provides you with access to the internet. Without them, you would not be able to send email or surf the world wide web. When you connect to your ISP, they will assign your computer one of their IP addresses. This IP address will be used to identify your computer while you are connected to the internet.

The WHP (or Web Host Provider, such as xeonbd.com) is a company that provides a means for individuals or businesses to publish a website on the internet. When the website is published, it is placed on a special computer known as a server that is connected to the internet via a high-speed connection. The WHP has already assigned this server one of their IP addresses.

Now, let’s summarize what we have learned so far by looking at a typical internet users experience:

Let’s say that you want to surf your newly published website. You connect to the internet and your computer gets an IP address (much like a phone number, a license plate, etc) from your ISP. You then open up your web browser and type in your website’s domain name: yourdomain.com.

Then you hit enter. Your computer sends a request. That request is blasted across the internet jumping through routers and gateways, across wires and beamed to satellites and back down to Earth again. After traveling several thousand miles in just a few milliseconds, it finally arrives at your WHP’s web server because it contains the IP address of the computer you are looking for.

The server then responds by sending a copy of the website’s home page back to your computer because it knows the IP address of the computer that made the request. You are now looking at your published home page in merely a few seconds and being proud of the pretty colors you picked for your menu buttons.

How did this all happen? Read on:

3. Domain Names.

A domain name is what you typically enter into your web browser when you want to visit a website. We also use them when sending email.

Website: www.yourdomain.com / Email: user@yourdomain.com

Domain names provide a fast and convenient way of reaching our favorite websites and sending email to each other. It is easy to remember the name of a friend’s website or a company that you like to shop with rather than trying to remember a number like: 64.247.43.26

What are we missing here? The mechanism that translates numbers into names (that is, IP addresses into domain names) and vice versa. Suspense….

4. Domain Name Registrar

If you want to have your own domain name you will need to register one through a company called a Domain Name Registrar. The domain registrar has tools that allow you to search for and register an available domain of your choosing. The registrar is more or less at the top of the whole naming scheme chain.

If you were able to read this far and even stay focus, congratulations – you ar a very determined individual. And now, as a reward for reading this much of my article, I will talk about… DNS, which is the topic you came here to read about in the first place.

5. DNS

DNS is a software program that runs on a dedicated computer known as a DNS server. DNS serves two primary functions:

1) To translate domain names into IP addresses.

It’s much easier to remember a domain like mydomain.com than a sixteen digit number like 64.247.43.26. DNS servers make translating or “Resolving” this information fast and seamless. When your computer needs to know the IP address for yourdomain.com it asks a DNS server (usually the one provided by your ISP.)

2) To act as authority for designated domain names.

Wherever you decide to host your website, the network you are on must have its own DNS servers. In fact, it is an industry-wide standard to have at least two DNS servers or more. These servers will act as the authority for your domain name because your network provider will put a special entry in their DNS server as it relates to your domain name that says: YOU ARE HERE! Technically this is known as an “A” record for “Authority”.

There are literally hundreds of thousands of these DNS machines world wide. They ARE the yellow pages of the internet and they contain information about your domain name. Keep in mind that no single DNS server holds all the domain names for the internet; they only hold the names that they are responsible for, and a few pointers to find the rest.

Some DNS servers strictly store names while others are doing the work of providing lookup services for computers that need to look up names. Many DNS servers do both. Technically, the server that is responsible for a particular domain is called the “Authority”. Remember the “A” record?

There are a few pieces of crucial information stored in a DNS server with regard to your domain name. This information as a whole is known as your “DNS Record”. In it you can find a variety of other pieces of information (or records) about your domain name. For the purposes of not altering your sanity, in this article I will focus only on the domain name, the record (or your WHP’s DNS servers).

6. The Propagation Process

As I said before, your domain registrar is the one responsible for publishing your domain name at the very first (called root) DNS level. When it is published, it is placed into a directory that is broadcast out to primary DNS servers around the world.

The primary DNS servers broadcast out to secondary DNS servers and so on and so forth.

This process is known as propagation and it can take upwards of 72 hours to complete. Propagation refers to the amount of time it takes for all the DNS servers everywhere around the world to recognize the fact that either a new domain is being registered, a domain name has been changed, or that the authority for that domain has changed.

Other reasons why it takes so long is obviously the size of our planet and the total number of DNS servers that require updated information. DNS servers are always updating themselves and changing dynamically during the course of any given day. When or why one DNS server will receive updated information before another is a complete mystery – really!

In most cases, your DNS propagation will complete well within the 72 hour period but you can’t be sure that everything is fine until you wait out the 72 hours! Once propagation is complete, anyone, anywhere on the internet should be able to visit your hosted website.

During that time you may experience strange occurrences. This is because not every DNS server that needs to know, knows about your domain name. Take your ISP for example. They use two DNS servers, well, 24 hours after making your nameserver changes, only one of your ISP’s DNS servers might receive the update regarding your domain name and the other might not.

If only one of these servers can resolve your domain to an IP address and the other can not, what you will experience would be as though your website was going up and down. One moment it is there, the next it is not.

Here is another example:

A friend of yours can see your new website and you can not. This is most likely because his ISP’s DNS servers are able to get the information at that time, where your ISP’s DNS servers can not.and wait another 72 hours. Ouch!

Here is a neat one:

You are transferring your hosting to a new WHP. During propagation you are working on development of some pages in your website. But you notice that when trying to view your most recent changes, they appear and then vanish or they don’t appear at all.

Think about the load-balancing DNS servers again. One server has information about your OLD WHP and the other has information about your NEW WHP! This can be a weird experience and may take some time to figure out. What you really need to do is WAIT OUT THE 72 HOURS!

You see, if you avoid making changes to your website during a transfer/propagation period, you will always have a consistent functional website available to your visitors. They won’t know that you have switched WHP’s because as far as they can tell, they are just browsing your website. They won’t realize that you are in a state of propagation and that from one minute to the next, they are potentially browsing your site from two different WHPs.

All of these occurrences are very common and each one of them will result in a phone call to the WHP asking why the server is going up and down. In reality the server is fine and your WSP is one of the finest. The problem is that the domain owner has not let 72 hours pass by, after which these and other similar problems will have vanished.

So as you can see, your Web Service Provider is not at fault, you just must have patience and wait the full three days before you can try to determine if your website is experiencing a problem or not.

Posted in: DNS Propagation, Domain Name Server(DNS), Domain Registration, General, Hosting Service

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