Category: Linux

I’ve realized so much over the past couple of weeks.

I created a serious drawback for myself. Having been a sysadmin for years and written a whole lot of articles and 5 books about Linux, I actually ought to have identified higher. Then once more, all of us make errors, which is a vital lesson: You are by no means too skilled to make a mistake.

I am not going to debate the main points of my error. It is sufficient to inform you that it was a mistake and that I ought to have put much more thought into what I used to be doing earlier than I did it. Apart from, the main points aren’t actually the purpose. Expertise cannot prevent from each mistake you are going to make, however it could aid you in restoration. And that is actually what this text is about: Utilizing a Reside USB distribution in addition and enter a restoration mode.

The issue

First, I created the issue, which was basically a nasty configuration for the /and so forth/default/grub file. Subsequent, I used Ansible to distribute the misconfigured file to all my bodily computer systems and run grub2-mkconfig. All 12 of them. Actually, actually quick.

All however two did not boot. They crashed through the very early phases of Linux startup with numerous errors indicating that the /root filesystem couldn’t be situated.

I may use the foundation password to get into “upkeep” mode, however with out /root mounted, it was unimaginable to entry even the only instruments. Booting on to the restoration kernel didn’t work both. The programs had been really damaged.

Restoration mode with Fedora

The one method to resolve this drawback was to discover a method to get into restoration mode. When all else fails, Fedora offers a extremely cool instrument: The identical Reside USB thumb drive used to put in new cases of Fedora.

After setting the BIOS in addition from the Reside USB system, I booted into the Fedora 36 Xfce reside consumer desktop. I opened two terminal classes subsequent to one another on the desktop and switched to root privilege in each.

I ran lsblk in a single for reference. I used the outcomes to establish the / root partition and the boot and efi partitions. I used certainly one of my VMs, as seen beneath. There isn’t a efi partition on this case as a result of this VM doesn’t use UEFI.

The /dev/sda1 partition is definitely identifiable as /boot, and the foundation partition is fairly apparent as properly.

Within the different terminal session, I carried out a sequence of steps to recuperate my programs. The precise quantity group names and system partitions akin to /dev/sda1 will differ to your programs. The instructions proven listed here are particular to my state of affairs.

The target is in addition and get by way of startup utilizing the Reside USB, then mount solely the required filesystems in a picture listing and run the chroot command to run Linux within the chrooted picture listing. This strategy bypasses the broken GRUB (or different) configuration information. Nonetheless, it offers an entire operating system with all the unique filesystems mounted for restoration, each because the supply of the instruments required and the goal of the adjustments to be made.

Listed here are the steps and associated instructions:

1. Create the listing /mnt/sysimage to offer a location for the chroot listing.

2. Mount the foundation partition on /mnt/sysimage:

# mount /dev/mapper/vg01-root /mnt/sysimage

3. Make /mnt/sysimage your working listing:

# cd /mnt/sysimage

4. Mount the /boot and /boot/efi filesystems.

5. Mount the opposite principal filesystems. Filesystems like /dwelling and /tmp usually are not wanted for this process:

6. Mount essential however already mounted filesystems that should be shared between the chrooted system and the unique Reside system, which remains to be on the market and operating:

7. You should definitely do the /dev listing final, or the opposite filesystems will not mount:

# mount --bind /dev dev

8. Chroot the system picture:

# chroot /mnt/sysimage

The system is now prepared for no matter it is advisable to do to recuperate it to a working state. Nonetheless, one time I used to be capable of run my server for a number of days on this state till I may analysis and take a look at actual fixes. I do not actually advocate that, however it may be an choice in a dire emergency when issues simply have to stand up and operating–now!

The answer

The repair was straightforward as soon as I received every system into restoration mode. As a result of my programs now labored simply as if they’d booted efficiently, I merely made the required adjustments to /and so forth/default/grub and /and so forth/fstab and ran the grub2-mkconfig > boot/grub2/grub.cfg command. I used the exit command to exit from chroot after which rebooted the host.

After all, I couldn’t automate the restoration from my mishap. I needed to carry out this complete course of manually on every host—a becoming little bit of karmic retribution for utilizing automation to rapidly and simply propagate my very own errors.

Classes realized

Regardless of their usefulness, I used to hate the “Classes Realized” classes we might have at a few of my sysadmin jobs, nevertheless it does seem that I have to remind myself of some issues. So listed here are my “Classes Realized” from this self-inflicted fiasco.

First, the ten programs that did not boot used a unique quantity group naming scheme, and my new GRUB configuration failed to think about that. I simply ignored the truth that they could presumably be completely different.

• Suppose it by way of utterly.
• Not all programs are alike.
• Check the whole lot.
• Confirm the whole lot.
• By no means make assumptions.

Every thing now works tremendous. Hopefully, I’m just a little bit smarter, too.

When you’re used to one operating system, it can be easy to look at other operating systems almost as if they were apps. If you use one OS on your desktop, you might think of another OS as the app that people use to run servers, and another OS as the app that plays games, and so on. We sometimes forget that an operating system is the part of a computer that manages a countless number of tasks (millions per second, technically), and they’re usually designed to be capable of a diverse set of tasks. When people ask me what Linux does, I usually ask what they want it to do. There’s no single answer, so here are five surprising things I do with Linux.

1. Laser cutting with Linux

At my nearest makerspace, there’s a big industrial machine, about the size of a sofa, that slices through all kinds of materials according to a simple line-drawing design file. It’s a powerful laser cutter, and I the first time I used it I was surprised to find that it just connected to my Linux laptop with a USB cable. In fact, in many ways, it was easier to connect to this laser cutter than it is to connect with many desktop printers, many of which require over-complicated and bloated drivers.

Using Inkscape and a simple plugin, you can design cut lines for industrial laser cutters. Design a case for your Raspberry Pi laptop, use these Creative Commons design plans to build a cryptex lockbox, cut out a sign for your shopfront, or whatever it is you have in mind.

2. Gaming on Linux

Open source has always had games, and there have been some high profile Linux games in the recent past. The first gaming PC I built was a Linux PC, and I don’t think any of the people I had over for friendly couch co-op games realized they were using Linux by playing. And that’s a good thing. It’s a smooth and seamless experience, and the sky’s the limit, depending on how much you want to spend on hardware.

What’s more is that it’s not just the games that have been coming to Linux, but the platform too. Valve’s recent Steam Deck is a popular handheld gaming console that runs Linux. Better still, many open source software titles have been publishing releases on Steam, including Blender and Krita, as ways to encourage wider adoption.

3. Office work on Linux

Linux, like life, isn’t always necessarily exciting. Sometimes, you need a computer to do ordinary things, like when you pay bills, make a budget, or write a paper for school or a report for work. Regardless of the task, Linux is also normal, everyday desktop computer. You can use Linux for the mundane, the everyday, the “usual”.

You’re not limited to just the big name applications, either. I do my fair share of work in the excellent LibreOffice suite, but on my oldest computer I use the simpler Abiword instead. Sometimes, I like to explore Calligra, the KDE office suite, and when there’s precision design work to be done (including specialized procedural design work), I use Scribus.

The greatest thing about using Linux for everyday tasks is that ultimately nobody knows what you used to get to the end product. Your tool chain and your workflow is yours, and the results are as good or better than what locked-down, non-open software produces. I have found that using Linux for the everyday tasks makes those tasks more fun for me, because open source software inherently permits me to develop my own path to my desired outcome. I try to create solutions that help me get work done efficiently, or that help me automate important tasks, but I also just enjoy the flexibility of the system. I don’t want to adapt for my tool chain, I want to adapt my tools so that they work for me.

4. Music production on Linux

I’m a hobbyist musician, and before I started doing all of my production on computers I owned several synthesizers and sequencers and multi-track recorders. One reason it took me as long as it did to switch to computer music was that it didn’t feel modular enough for me. When you’re used to wiring physical boxes to one another to route sound through filters and effects and mixers and auxiliary mixers, an all-in-one application looks a little underwhelming.

It’s not that an all-in-one app isn’t appreciated, by any means. I like being able to open up one application, like LMMS, that happens to have everything I want. However, in practice it seems that no music application I tried on a computer actually had everything I needed.

When I switched to Linux, I discovered a landscape built with modularity as one of its founding principles. I found applications that were just sequencers, applications that were just synthesizers, mixers, recorders, patch bays, and so on. I could build my own studio on my computer just as I’d built my own studio in real life. Audio production has developed in leaps and bounds on Linux, and today there are open source applications that can act as a unified control center while retaining the extensibility to pull in sounds from elsewhere on the system. For a patchwork producer like me, it’s a dream studio.

5. Retro computing on Linux

I don’t like throwing away old computers, because very rarely do old computers actually die. Usually, an old computer is “outgrown” by the rest of the world. Operating systems get too bloated for an old computer to handle, so you stop getting OS and security updates, applications start to demand resources your old computer just doesn’t have, and so on.

I tend to adopt old computers, putting them to work as either lab machines or home servers. Lately, I find that adding an SSD drive to serve as the root partition, and using XFCE or a similar lightweight desktop, makes even a computer from the previous decade a pleasantly usable machine for a lot more work than you might expect. Graphic design, web design, programming, stop-motion animation, and much more, are trivial tasks on low spec machines, to say nothing of simple office work. With Linux driving a machine, it’s a wonder businesses ever upgrade.

Everybody has their favorite “rescue” distribution. Mine are Slackware and Mageia, both of which still release 32-bit installer images. Mageia is RPM-based, too, so you can use modern packaging tools like dnf and rpmbuild.

Bonus: Linux servers

OK, I admit Linux on servers isn’t at all surprising. In fact, to people who know of Linux but don’t use Linux themselves, a data center is usually the first thing that pops into their heads when “Linux” is mentioned. The problem with that assumption is that it can make it seem obvious that Linux ought to be great on the server, as if Linux doesn’t even have to try. It’s a flattering sentiment, but the fact is that Linux is great on servers because there’s a monumental effort across global development teams to make Linux especially effective at what it does.

It isn’t by chance that Linux is the robust operating system that powers most of the internet, most of the cloud, nearly all the supercomputers in existence, and more. Linux isn’t stagnate, and while it has a rich history behind it, it’s not so steeped in tradition that it fails to progress. New technologies are being developed all the time, and Linux is a part of that progress. Modern Linux adapts to growing demands from a changing world to make it possible for systems administrators to provide networked services to people all over the world.

It’s not everything Linux can do, but it’s no small feat, either.

[ Red Hat Enterprise Linux turns 20 this year: How enterprise Linux has evolved from server closet to cloud ]

Linux isn’t that surprising

I remember the first time I met someone who’d grown up using Linux. It never seemed to happen for most of the time I’ve been a Linux user, but lately it’s relatively common. I think the most surprising encounter was with a young woman, toddler in tow, who saw whatever geeky t-shirt I was wearing at the time and casually mentioned that she also used Linux, because she’d grown up with it. It actually made me a little jealous, but then I remembered that Unix on a desktop computer simply didn’t exist when I was growing up. Still, it’s fun to think about how casual Linux has become over the past few decades. It’s even more fun to be a part of it.