Category: Networking

Let’s Find A Site’s MX Records

Today’s article is going to be rather specific and brief, as we learn how to find a site’s MX records. This isn’t something everyone is going to need to know, but it’s useful for debugging an email issue when you’re hosting websites. So, some folks are going to find it useful – and will then know how to find a site’s MX records. Read on!

I suppose most of my readers will not know what an MX record is…

In short, an MX (Mail Exchange) record is another DNS (Domain Name System) record. In this case, it is used to route emails to the correct server (via the IP address, basically). From there, your server will route the emails to individual email inboxes.

Basically, you want to know this information when things go pear-shaped with your emails or maybe when you’re using a 3rd party email service provider. There are reasons why people will want this information, they will want to find a site’s MX records.

Additionally, I figured I’d do this article now while ‘dig’ is still fresh in our memory. After all, I’ve used dig in the previous two articles and this is the final dig-related topic that I can think of. Here are the previous two articles, if you’re not reading these articles in order and are unfamiliar with the dig command:

How To: Find A Website’s IP Address
How To: Find A Site’s Nameservers

So, with all that in mind, let’s learn how to find a site’s MX records!

How To Find A Site’s MX Records:

Yes, dig is run in the terminal. Yes, you’ll need an open terminal to follow along. If you don’t know how to open the terminal, you can do so with your keyboard – just press CTRL + ALT + T and your default terminal should open.

With your terminal now open, the syntax for this specific dig command is:

For example, you’d find this site’s MX records with:

If you want, as the other dig commands used recently, you can use the +short flag with this, like so:

The output should look like this:

using the dig command to find a site's MX records
There, you can see this site’s MX records. This is public information. So, gawk away!

You can have more than one MX record, should you want failover but the mail protocol already includes some efforts to resend mail when there’s an outage. That’s irrelevant here, but information that I might as well share.

Also, like the other dig commands covered, you can put the flags at the end, like so:

So, that’s an option. I’m not sure why it’s an option. If anyone has a clue as to why it’s an option, do feel free to share. Heck, even if it’s a wild guess, I’ll take it. But, if you want more information about the dig command, run man dig in your terminal.

Closure:

There you have it, it’s another article. I think this is the last dig article, but who knows? This time around, we’ve learned how to find a domain’s MX records. For those that need to know, this will be handy.

For everyone else, you’ll likely forget this by tomorrow – and that’s okay. You don’t have to carry all the tools in your toolbox. If you tried, you’d need a very big toolbox and it’d be hard to carry it!

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

How To: Find A Site’s Nameservers

Today’s article will be a fun and easy one if you already understand nameservers, as I will be explaining how to find a site’s nameservers. If you don’t understand nameservers, it may be a bit more difficult. But, I’ll do my best to make it approachable. So, to learn how to find a site’s nameservers read on!

Okay, so what are nameservers?

Hmm… Let’s try to explain it in the most simple way possible… 

DNS is like a phone book. You look in the book to see which number (IP address) to connect to. However, just like in the real world (though less common with cell phones) a given telephone number may belong to multiple people.

Nameservers help to organize those DNS records. Using the nameservers is sort of like calling a phone exchange and then entering a party’s extension number to go directly to that person.

Does that make sense? No? Well, that’s the best you’re getting. I suck at analogies unless they’re automotive-related and I can’t come up with one that makes sense. I’m pretty sure the above was how it was first explained to me, or something like that. Ah well…

It should be pointed out that I used ‘dig’ in the previous article. We’ll be using that again. This time, we’ll be using dig to find a site’s nameservers instead of the site’s IP address. We might as well learn about it now, while the dig command is fresh in our memories!

Find A Site’s Nameservers:

This article requires an open terminal, like many other articles on this site. If you don’t know how to open the terminal, you can do so with your keyboard – just press CTRL + ALT + T and your default terminal should open.

With your terminal now open, the syntax for finding a site’s nameservers is as follows:

Or, if you prefer a shorter output, you have:

Like the previously used dig command, you can actually put the flags at the end (if that’s something you feel like doing). It works just fine like:

If we use this site as an example, the outcome of the latter command should look something like this:

using dig to find a site's nameservers
And there you see them, this site’s nameservers as shown by dig. Pretty easy, huh?

As you can see, nameservers look just like domain names. You’ll also note that those (shouldn’t) don’t change, unlike the site’s IP address. As we’re using a CDN, there are a number of possible IP addresses. The nameservers will be the same no matter what part of the globe you connect from.

Of course, there’s more to the dig command. We’ve just touched on a couple of uses. Check the man page with man dig to find out what other options are available.

Closure:

Well, there you have another article. Once again, we’ve used dig in this article. I figured we might as well have another dig article while I was thinking about it, and this time we used dig to find a site’s nameservers. Hopefully, this will be useful for you at some point in your Linux journey. As I deal with a bunch of websites, it’s important for me to know my nameservers and to know when they’ve propagated (something for another article).

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your own site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

How To: Find A Website’s IP Address

Today’s article should be interesting, as we learn how to find a website’s IP address. There’s more than one way to do this sort of thing, so I’ll just be showing you the one way to do so. I want to keep it relatively short and simple. So, to find out how to find a website’s IP address, read on!

I have a reason to keep this one short and simple. I’m in the midst of a blizzard and am likely to lose my connection at some point this evening. That’s okay, I love the cold and snow. As for me and my house, I’ve got solar and wind. I won’t want for anything. I’ve been out playing in the snow already. I’ll go back out shortly.

So, let’s say you want to know the IP address of your favorite website. That’s easy enough to learn. Though it may surprise you that your favorite website might have multiple IP addresses. That’d often be because many websites have multiple nameservers pointing at them for a bit of redundancy.

We’ll be using the ‘dig’ tool. This is likely installed by default. You shouldn’t need to install anything. The dig command defines itself as:

dig – DNS lookup utility

That’s what we’ll be using to find a website’s IP address, as it’s a fine tool for doing so. With that said, let’s just jump into the article…

Find A Website’s IP Address:

If you’re a regular reader, you know that it’s probably time to open a terminal. Like many articles, this one requires an open terminal, as that’s where you use the dig command. Just press CTRL + ALT + T and your default terminal should open.

With your terminal open, we’ll use Linux Tips as our example:

The output of which should look like this:

using dig to find a website's ip address
You’d be looking for the answer section, as indicated in the graphic. Pretty easy, huh?

As you can see, the answer section is what you’re looking for. The IP addresses are on the right. As you can see, this site has two IP addresses – both of which belong to my CDN (if you’re curious).

You can save some time and space… Well, some space. I suppose it may take you a second or so longer to type out the extra characters. But, give it a try with the +short flag (placed in a weird spot).

The output from that command is a bit easier and more concise:

using +short is a neater output to find a website's ip address.
That’s a bit easier and contains just the information you’re looking for. You can just use that.

You can use either or both, depending on what you’re after. I suppose it’s technically a bit longer when you type in the last command, but your output is just the information you’ve been looking for.

By the way, dig +short linux-tips.us will work, I just learned it the other way, so that’s how it is situated in my notes. If you’re feeling weird about placing the flag at the end of the command, just place it where flags normally go. Also, don’t forget to check the man page with man dig for more information about the dig command.

Closure:

And there you have it, you have another article! This time we’ve covered how to find a website’s IP address. If the site has a dedicated IP address, you can use that IP address to connect to the site, as opposed to using the domain name. So, there’s that…

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Make ‘wget’ Resume From An Interrupted Download

Today’s just going to be a quick article, an article where we learn how to make ‘wget’ resume from an interrupted download. This is a darned useful function you can add to a wget command, especially if you’re in an area with sketchy connectivity. To learn to make wget resume from an interrupted download, read on!

So many of my articles are written because of something I did recently. Many are still based on my copious notes (we’re well over 300 articles here on Linux Tips), but those will run out eventually. I’m often thinking of new ideas for articles and sometimes my day-to-day computing gives me an article idea that’s not from my notes. This is one of those…

Today, we’re going to cover yet another wget feature! We’ve had many wget articles. Here are a few of them:

Limit The Download Speed For ‘wget’
Rename A File Downloaded With ‘wget’
How To: Hide The Output From wget

And we’ve used wget in many articles. Go search for “wget”.

By now, many of my regular readers will be more than familiar with wget. So, what is wget? It’s a terminal-based tool that you use to download files. I use it often. You’re encouraged to check man wget for more information.

I use it outside of the browser, even if I found the download link via a browser. It’s just that handy and the throughput rate seems to be greater with wget (oftentimes). If you check the man page, wget describes itself as:

The non-interactive network downloader.

Which is exactly what it does. Which is nice…

How To: Make ‘wget’ Resume From An Interrupted Download:

You’ll kinda sorta maybe need an open terminal for this article. If you don’t know how to open the terminal, you can do so with your keyboard. Press CTRL + ALT + T and your default terminal should pop open.

With your terminal open, you just need a file to download… I’ll let you pick that. You also need to interrupt your download, so that you can practice this…

Wait, no… That’s just silly. Instead of practicing this, just learn from my usage and call it good. There’s no need to replicate this until you need it. Yeah, that’s the ticket!

So, imagine my surprise when I learned that Gentoo now has a live USB edition. (I was pretty surprised.) I immediately decided to download the file, though I’ve still not tried it. To download the .iso, I used the fantastic wget tool.

My terminal was already open. My present working directory was already the ‘Downloads’ directory. I had nothing to do except enter the wget command. The command I entered was this:

As you may know, my DSL provider made me angry and I’m now using a combination of a mobile hot spot and satellite. My mobile provider likes to disconnect me for 30 minutes at a time and does so at varied intervals.

I normally just switch to the satellite connection for 30 minutes but wget didn’t like that. I’d already downloaded half of the file while tethered to my phone and didn’t want to download it again. Downloading data I’d previously downloaded is just a pain in the butt and slows things down. So, I added the -c flag. The command I then used, once connectivity was restored, was this:

Sure enough, wget resumed from where it left off when the connection dropped out. I didn’t have to download that all over again. Sure, wget will automatically retry a few times (which you can modify) but it’s not going to keep trying for 30 minutes (by default) or longer. So, this is how you make wget resume from an interrupted download.

Closure:

See, it’s easy to make wget resume from an interrupted download. Was it worth writing an entire article for a single flag? I’d say yes. Well, of course, I would say yes. If I didn’t think it was worth an entire article, I wouldn’t have written an entire article about it!

Ah well…

And now you know…

You’re welcome…

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

A Couple More Ways To Find Your Network Interfaces

Today’s article is mostly just for fun, as we examine a couple more ways to find your network interfaces! I’ve shown you a variety of ways at this point, but this is Linux. If you just want to have some fun finding your network interfaces, read on – ’cause this article is meant for those who like to travel a different path!

One of the things that make Linux so awesome is the myriad choices we have. There are so many different ways to accomplish the same goal. In fact, we sometimes get defensive about ‘our way’ of accomplishing things. It can make for some amusing (and sometimes a bit heated) discussions. 

Anyhow, I’ve covered this before. I’ve even covered it recently, which is why this is still fresh in my memory. You can start with this article if you want:

How To: Show Your Network Interfaces

Just to touch on it, a network interface is a device that your computer uses to communicate over the network. In most folks’ cases, you’ll locally use your network interface to connect to the Internet, perhaps first to your router or modem. These networking devices have names.

It’s important to be able to point to a specific networking interface, which is why they have names. If you want to issue commands, you want to send them to the right networking interface. If you want to monitor a connection, you need to know the correct name for the network interface.

So, these network interfaces have names. These names should be unique in your system, meaning you shouldn’t have more than one device per name. The names should not be shared among the devices and each working networking interface should have a name of its own.

If you want to know the network interface names, this article’s for you…

Find Your Network Interfaces Continued:

This article requires an open terminal, like many other articles on this site. If you don’t know how to open the terminal, you can do so with your keyboard – just press CTRL + ALT + T and your default terminal should open.

With your terminal now open, we’re going to show you a couple of new ways to find your network interfaces. It’ll be fun!

For starters, and probably one I should have already covered, we’ll use a command we’ve covered here and here. We’ll use the ‘netstat’ command, and the ‘netstat’ command you need to find your network interfaces is simply:

(If you don’t have ‘netstat’ available, install the ‘net-tools’ package from your distro’s repositories. It’s almost certainly available.) The output is nice and clear and will show you the names of your network interfaces.

The next command we’ll use is one we’ve used many times before. It’s just a two-letter command, so trying to search for it (on this site) is neigh on impossible – but you can be certain that we’ve used it before. (We’ve at least covered sorting and formatting the output from the ‘ls’ command.)

Anyhow, the command we’ll use to list the network interfaces is pretty simple, it’s just this simple command:

That ‘ls’ command should spit out a list of your network interfaces all nice and easy. If there’s going to be one command that’ll work on any system, it might be this one.

Speaking of which, as this is Linux, there are all sorts of ways to accomplish goals. Because of this, that also means they’ll not always work on every system. You may need to try multiple commands to get the output you’re after – but both of today’s commands should result in you getting the names of your network interfaces (even if you have to install ‘net-tools’ to do so).

Closure:

There you have it, another easy article. Ugh… I do wish I was feeling a bit more up to snuff. Meh… At least I’m writing and writing this sort of stuff. In this case, it’s another article that’ll show you how to find your network interfaces. It’s information worth having. They’re tools that will go well in your growing toolkit of Linux tools.

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your own site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Subscribe To Our Newsletter
Get notified when new articles are published! It's free and I won't send you any spam.
.
Linux Tips
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.