Have you ever heard a colleague answer the phone like this: “Good afterno… Yes… What? Completely?… When did it go down?… Really, that long?… We’ll look into it right away… Yes, I understand… Of course… Okay, speak to you soon… Bye.”
The call may have been followed by some cheesy ’80s rock ballad coming from the speaker phone, interrupted by “Thank you for holding. You are now caller number 126 in the queue.” That’s your boss calling the hosting company’s 24 hour “technical support” line.
An important website has gone down, and sooner or later, heads will turn to the Web development corner of the office, where you are sitting quietly, minding your own business, regretting that you ever mentioned “Linux” on your CV. You need to take action. Your company needs you. Your client needs you. Here’s what to do.
1. Check That It Has Actually Gone Down
Don’t take your client’s word for it. Visit the website yourself, and press Shift + Refresh to make sure you’re not seeing a cached version (hold down Shift while reloading or refreshing the page). If the website displays fine, then the problem is probably related to your client’s computer or broadband connection.
If it fails, then visit a robust website, such as google.com or bbc.co.uk. If they fail too, then there is at least an issue with your own broadband connection (or your broadband company’s DNS servers). Chances are that you and your client are located in the same building and the whole building has lost connectivity, or perhaps you have the same broadband company and its engineers have taken the day off. You will need to check the website on your mobile phone or phone a friend. To be doubly sure, ask your friend to check Where’s It Up? or Down for Everyone or Just Me?, which will confirm whether your website is down just for you or for everyone.
If the website is definitely down, then frown confusedly and keep reading. A soft yet audible sigh would also be appropriate. You might want to locate the documents or emails that your Internet hosting service sent you when you first signed up with it. It should have useful details such as your IP address, control panel location, log-in details and admin and root passwords; these will come in handy.
2. Figure Out What Has Gone Down
A website can appear to have gone down mainly for one of the following reasons:
- A programming error on the website,
- A DNS problem, or an expired domain,
- A networking problem,
- Something on the server has crashed,
- The whole server has crashed.
To see whether it’s a programming error, visit the website and check the status bar at the bottom of your browser. If it says “Done” or “Loaded,” rather than “Waiting…” or “Connecting…,” then the server and its software are performing correctly, but there is a programming error or misconfiguration. Check the Apache error log for clues.
Otherwise, you’ll need to run some commands to determine the cause. On a Mac with OS X or above, go to Applications → Utilities and run Terminal. On a PC with Windows, go to Start → All Programs → Accessories and choose “Command Prompt.” If you use Linux, you probably already know about the terminal; but just in case, on Ubuntu, it’s under Applications → Accessories.
The first command is ping, which sends a quick message to a server to check that it’s okay. Type the following, replacing the Web address with something meaningful to you, and press “Enter.” For all of the commands in this article, just type the stuff in the grey monospaced font. The preceding characters are the command prompt and are just there to let you know who and where you are.
C:> ping www.stockashop.co.uk
If the server is alive and reachable, then the result will be something like this:
Reply from 92.52.106.33:
bytes=32 time=12ms TTL=53
Ping command from a Windows computer.
On Windows, it will repeat four times, as above. On Linux and Mac, each line will start with 64 bytes from and it will repeat indefinitely, and you’ll need to press Control + C to stop it.
The four-part number in the example above is your server’s IP address. Every computer on the Internet has one. At this stage, you can double-check that it is the correct one. You’ll need to have a very good memory, or refer to the documentation that your hosting company sent you when you first signed up with it. (This article does not deal with the newish eight-part IPv6 addresses.)
For instance, my broadband company is sneaky and tries to intercept all bad requests so that it can advertise to me when I misspell a domain name in the Web browser. In this case, the ping looks successful but the IP address is wrong:
64 bytes from advancedsearch.virginmedia.com
(81.200.64.50): icmp_seq=1 ttl=55 time=26.4 ms
Note that ping might also show the server name in front of the IP address (advancedsearch.virginmedia.com in this case). Don’t worry too much if it doesn’t match the website you are pinging—a server can have many names. The IP address is more important.
Assuming you’ve typed the domain name correctly, a bad IP address indicates that the domain name could have expired or that somebody has made a mistake with its DNS settings. If you receive something like unknown host, then it’s definitely a domain name issue:
ping: unknown host www.nosuchwebsite.fr
In this case, use a website such as Who.is to verify the domain registration details, or run the whois command from Linux or Mac. It will at least tell you when it expired, who owns it and where it is registered. The Linux and Mac commands host and nslookup are also useful for finding information about a domain. The nslookup command in particular has many different options for querying different aspects of a domain name:
paul@MyUbuntu:~$ whois stockashop.co.uk
paul@MyUbuntu:~$ host stockashop.co.uk
paul@MyUbuntu:~$ nslookup stockashop.co.uk
paul@MyUbuntu:~$ nslookup -type=soa stockashop.co.uk
If nothing happens when you ping, or you get something like request timed out, then you can deepen your frown and move on to step three.
What a non-responding server looks like in a Linux terminal.
Alternatively, if your server replied with the correct IP address, then you can exhale in relief and move on to step five.
Note that there are plenty of websites such as Network-Tools.com that allow you to ping websites. However, using the command line will impress your colleagues more, and it is good practice for the methods in the rest of this article.
3. How Bad Is It?
If your ping command has timed out, then chances are your whole server has crashed, or the network has broken down between you and the server.
If you enjoy grabbing at straws, then there is a small chance that the server is still alive and has blocked the ping request for security reasons—namely, to prevent hackers from finding out it exists. So, you can still proceed to the next step after running the commands below, but don’t hold your breath.
To find out if it is a networking issue, use traceroute on Mac or Linux and tracert on a PC, or use the trace option on a website such as Network-Tools.com. On Mac and Linux type:
paul@MyUbuntu:~$ traceroute www.stockashop.co.uk
On Windows:
C:> tracert www.stockashop.co.uk
Traceroute traces a route across the Internet from your computer t
Reference: http://ping.fm/Kkbsl
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