Tag: time

Change Your Timezone In Linux

Today’s article is an easy one about how you can change your timezone which isn’t something you’ll likely need to do all that often. It’s not all that complicated, though it can look like it is. It can be a bit tedious, but that’s just at first blush. I’ll show you how to make it a bit easier.

NOTE: This is actually a duplicate. I wrote it some time ago and realized it was a duplicate, or reasonably close to another article. I decided to save it and publish a duplicate article when an ’emergency’ came up. Well, we have an ’emergency’. I had too many adult beverages before it was time to write a new article. So, you get this one.

Now, the title is obviously not correct. You’re not going to change your timezone, you’re going to change the timezone settings your computer is using. Alas, headlines aren’t to be all that long and are allowed to make some assumptions. If you want to change your timezone, you’ll have to move.

This article is only useful to you if you use systemd.

My regular readers may have noticed a giant outage. Linux-Tips.us was unreachable for a good part of the 6th. My initial assumptions were that we’d been hacked, that is that WordPress had become compromised. That’s a reasonable assumption.

It turns out that we’d been moved to a new data center. We’re now located in New York. I use a CDN that relies on an IP address. There are a bunch of DNS records behind the scenes. Those records had to be updated. That wasn’t a major task, but troubleshooting the problem was the challenge.

Everything turned out okay and I won’t even miss a scheduled publication. Of course, I’m writing this at 04:45, but you will have your article today. So far, I haven’t missed a publication date. I’m quite amazed by this.

Speaking of today’s article, we’re going to be learning how to change your timezone. We’ll be doing this in the terminal and the tool we’ll be using is known as timedatectl. If your distro uses systemd, you have this installed. When you check the man page (with man timedatectl) you’ll see that timedatectl defines itself as:

timedatectl – Control the system time and date

As you can see, this is probably the right tool for the job – assuming the job is changing your timezone. Seeing as that’s what the title says we’ll be doing, we might as well do that.

Change Your Timezone:

As mentioned in the introduction portion of this article, you’ll be doing the work in the terminal. It’s often easy to open a terminal with a keyboard shortcut. Frequently, you can open your default terminal by just pressing CTRL + ALT + T. Otherwise, look in your application menu. That’d be a good spot to look for a way to open your terminal.

With your terminal open,  you can enter the following command to see what you have for your current timezone settings:

Before you can change your timezone you have to know what time zones are available. There are a whole lot of them, meaning you can be scrolling for quite a while. Go ahead and enter this command:

(You can press CTRL + C to get out of that.)

So, what we’re going to do is narrow down the results shown to you. You’ll need to know the region you’re in, such as Europe, Africa, America, etc for this next part and we’re going to use a pipe and grep (which we’ve used in the past). For me, I’d want to set my timezone to New York in America and my command would look like:

You’ll note that this is case-sensitive. Listed in the output would be the text I’m after, the text needed for the command that lets you change your timezone. It looks like this:

With that information available, I can now complete the command to change my timezone to that of New York. That command is easy enough. It just looks like:

Or, when using my location as the example, the command looks like this:

It’s not too daunting a task to change your timezone. If you entered the wrong timezone during installation, you can trivially change it to the correct timezone.

I should mention that your computer will use NTP to keep your system’s clock set. This is also stored in your system’s hardware. The CMOS battery keeps that and other settings stored while the power is disconnected. This battery can go bad.

If that battery does go bad, you may find yourself setting the date and time of your system every time you start your computer. NTP should then kick in and keep your system’s time updated. For reasons deeper than this blog will go, your system depends on time (specifically Unix Time) in all sorts of applications.

Closure:

Well, there was some drama. The site was down for an extended period and this article wasn’t written until the wee hours of the morning. However… However, I didn’t miss a publication date. Also, I just realized I haven’t done a meta article in a while.

With some great help from the hosting company upstream, everything was resolved and you got an article about how to change your timezone in Linux. All’s well that ends well.

While there are backups, my heart sank when I thought that the site had been hacked. Cleaning that mess would have been tedious. Fortunately, that wasn’t required. No data was lost and we can move on knowing that it’s just a footnote in the site’s history.

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 Applications Start Faster in Ubuntu

Today’s article is pretty specific as we discuss one way to make applications start faster in Ubuntu. However, I feel like I need to make you aware that this isn’t some sort of miracle software. The usage and results are pretty limited and I’m mostly covering this because it was in my notes and a question I saw recently on Reddit.

Now, for reasons, I’m not sure what format this article will take. I haven’t written it yet and the information I want to share is kinda mixed. I guess we could have a longer intro than normal.

So, the tool in question is called ‘Preload’. The man page describes Preload like this:

preload – Adaptive readahead daemon

Though I think it’s important to also quote this (also from the man page):

preload is an adaptive readahead daemon that prefetches files mapped by applications from the disk to reduce application startup time.

So, what is this Preload? It’s a daemon that runs in the background and monitors what you do. It pays attention to what applications you open (for example) and loads the various files into memory. Then, when you open the application it will open faster. This is mostly useful if you’ve opened the application, closed it, and wish to open it again. The second time you open the application, the theory is that it’ll open faster.

Does it work? I haven’t lied to you yet and I’m not going to start now. I haven’t tested it enough to claim it has any great benefits. Oh, I’ve installed it before and left it running. I just didn’t do any verification and I’m not going to cite my observations as factual without having data to back that up. I will say that I didn’t notice it slowing anything down. Of course, I have fast hardware, and using a stopwatch to test the results would be full of all sorts of inaccuracies. 

Do I recommend it? Well, it doesn’t seem to hurt anything. It does seem faster when I close Thunderbird and open it back up again. I use an NVMe M.2 SSD, which is already pretty speedy, so I doubt I’d see much. I’ve never tried with a slower SSD nor on an older spinning platter HDD – which is where I’d expect this Preload to work best. If you’re using older disks, it may be worth trying Preload. But, you won’t break anything if you install it on more modern hardware.

Make Applications Start Faster:

So, installing Preload is pretty simple. Once you’ve installed Preload, you are done. There’s no need to tinker with settings. There’s no need to configure it. It should even automatically set itself up as a self-starting daemon.

Crack open your terminal (you know how to do that by now) and enter the following to install Preload in Ubuntu:

Agree to install and enter your password. That’s it. That’s all you need to do. You can check the man page:

See? I told you this would look like a weird article.

Closure:

Have you had good luck with Preload? Have you been using it all along? Did you use it back when you were using a spinning hard drive? Did it help to make applications start faster? Let me know in a comment. I mean, it’s not snake oil, but how much could it help an average user with modern hardware? I’m not sure how much it’ll help those folks.

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.

Let’s Play With Touch And Time

Today’s article is just a fun article where we get the chance to play with touch and time. This article won’t necessarily be something you rely on daily, but it should at least be informative. That and there’s surely a subset of users who use these commands. There’s bound to be! Otherwise, why would they make touch flags for adjusting the time?!?

We’ve used the ‘touch’ command before.

Some Useful Ways To Use The Touch Command In Linux

I’m pretty sure we’ve also used the touch command in at least another article. There are a lot of search results for the word and it’s not important enough to go looking. The key point is that touch is a command you use in the terminal and it describes itself as:

touch – change file timestamps

See, we (and perhaps most other sites) have used the touch command to *make* files, but it’s useful (and intended for) changing file timestamps. Like oh so many commands, there are all sorts of ways to use it and so many folks do things in their own way. The great thing about Linux is that we have so many choices.

This is why I figure I’ll cover touch and time in this article. It’s just a few commands that we’ll be using, so it’s not all that advanced. A beginner probably won’t need to know this sort of information, but it’s information worth sharing.

Playing With Touch And Time:

As we use touch in the terminal, you’re going to need to have an open terminal to play with touch and time. If you don’t know how to open a terminal, press CTRL + ALT + T and your default terminal should open.

With your terminal now open, let’s start by creating a file:

That command will create a file with a created timestamp from the time you ran the command. If you want, you can change the access time, that is the time stored with the file that says when it was last accessed. Run the following command with the -a flag:

That’ll change the ‘foo file’s access time to the time when you ran the command. All well and good? Alright… Let’s remove that file with:

Now, we’re going to create the foo file again, but we’re going to give it a specific timestamp. The format you want is:

Or, something like this:

That will give the file a timestamp from March 3rd at one minute and one second past midnight. Note the period denoting seconds as that’s the only modifier you need for this command.

NOTE: If you use a different time format, that command might be different for you. I don’t think it is, but I’m not set up to test that. If it does matter, please let us know in a comment, thanks!

Finally, let’s say you have a file named ‘bar’ and you want ‘foo’ to have the same timestamp that bar has. You can do that with the touch command. It’s relatively easy to do with the -r flag:

That command will give foo the same timestamp that bar has, should you be inclined to do so. It’s pretty easy to use the touch command to change a timestamp on files, which is why you might not want to rely too much on timestamps. They can be useful, but they are not immutable. 

You can run the command above to delete the foo file when you’re done playing around with the touch command:

Closure:

There you go, another article. This time, we’ve had an article about using touch and time, which is kinda why the touch command exists in the first place. It’s far more useful than just creating files. Be sure to run man touch (no inappropriate jokes) in the terminal to learn more about the touch command. There are other touch commands that you may find yourself interested in, I’ve just covered a few of them.

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.

Find Your Linux System’s Timezone

This article, telling you how to find your system’s timezone, is more aimed at server users than desktop users. Desktop users probably know this already.

This command is most useful when you’re dealing with servers across the globe. You may want to schedule things (for one small example) to run at local times and knowing the local time will help with that. Knowing the timezone is pretty important, and the timezone itself is important.

The timezone dictates things like when your clocks change to adjust for Daylight Savings Time. While that may not seem like a big deal, having the proper date and time is a big deal. So, this article will tell you a couple of quick and easy ways to find your Linux system’s timezone.

Find Your Linux System’s Timezone:

This is going to need an open terminal. You probably could have guessed that. You can open a terminal with your keyboard – just press CTRL + ALT + T and your default terminal should open.

With your terminal open, you can try one of the following commands (I prefer the first):

The second option is easier to remember, but you don’t get the full name of your timezone. It may require a bit more thinking, just to be sure. Try:

And the timezone will be at the end of that string of characters. If you’re still confused, you can type the abbreviation into your favorite search engine and they’ll get you sorted out.

Thee is a third way, but keeping that way crammed into memory isn’t as easy as the date command. It’s just:

Of course, you can just use ​’timedatectl’ without grep. That’s a viable option, it just spits out more information. So, if you were to remember just one of the commands, the third one is probably the best.

Those are three ways I know of to find the timezone within the Linux terminal. It may show up in the GUI. If you want to add it to your system’s time display, you add %Z to the string (ISO 8601 standardizes this) and it’d look something like this when you changed it and the change took place:

Using the #Z to show the timezone in the system clock.
Tada! That’d be how you’d do that!

So, you can display the timezone in the GUI if you really needed to. But, this article is mainly for those who admin servers across the globe and need to know the timezone the system is in.

Closure:

Woohoo! Another article done and ready to publish. However, I’m going to leave this one unscheduled (scheduled way in the future) so that I have an ’emergency’ article, an article that can be used when Mother Nature has taken out my ‘net or motivation just isn’t there.

Either way, this article covered how to find your timezone in Linux. It’s information you may want, and information you may want to check before rolling out changes. The data is in the system, we just need to pry it out.

Show Date And Time In The Terminal

Today’s article is a nice and easy one, where I show you how to show the date and time in the terminal. It seems like a nice and easy article to write when I’m not feeling well. I’ll try to not let my ailments hamper the article in any way. 

Normally, I’d have a few articles written ahead of time. This time, I only have one article written ahead of time and it’s my ’emergency’ article. I’m not doing that poorly, so I’ll write this one. I’m pretty dedicated to doing an article every other day.

Anyhow, as I said, this article will show you how to get the date and time from the terminal. You can actually get the time just from running uptime, but there’s more to it. Linux actually has a ‘date’ command, which is what we’ll be using for this exercise. The date command’s man page describes it like:

date – print or set the system date and time

We will only be using the date command to print the time in the terminal. There are easier ways to set and maintain the time. With NTP being common, you really shouldn’t have to worry much about keeping the time accurate enough on your system.

Why would you want to know the date and time? Not everyone uses a desktop environment with a GUI and a clock. You may need to know the system time when you’re working on it remotely. There are all sorts of reasons. In fact, I once wrote an entire article about finding your timezone in Linux.

Show Date And Time In The Terminal:

This article requires an open terminal, just like many other articles on this site. Just press CTRL + ALT + T and your default terminal should open.

Now, this is nice and obvious… With your terminal open, just type in:

You’ll get an output similar to this one:

Tada! You’re done!

Just kidding! There’s more to it. If you want to show just the time, you can just use this command:

If you want to show the date and have it formatted like we do in the US, you can use this command:

Want to know the date 3 weeks ago? (You can also use days for this command)? Well then, you can try this command:

How about if you want to know how many days into the year you are? Well, you can do that with:

Those are about the most interesting ways to show the date and time in the terminal, at least the most interesting ways that I can think of at this moment in time. If you use the date command for anything else, let us know by leaving a comment!

Closure:

There you have it, yet another article! This one shows you how to show the date and time in the terminal, just in case you want to do that. It’s a nice and easy exercise and, as far as tools go, is one that’s at least easy to remember. It’s probably not the most important tool you can have in your toolbox, but at least it’s in there. (Please be gentle pointing out any errors, part of this article was written with the help of a heating pad.)

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.

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