
Errata for Using and Administering Linux — 2nd Edition
Last Updated on June 11, 2025 by David Both
This page contains errata for the 2nd Edition of my Using and Administering Linux three-volume set of books.
I’m sure there are more errors than have been reported so far. If you encounter an error, please email me at LinuxGeek46@both.org. I’ll keep this as up to date as possible.
Volume 1
- Page 99-100: Although I suggest using an external USB storage device for your experiments, you can also use an internal device that has at least 300GB of storage available and which can be partitioned and allocated for use by the virtual machines. Depending upon the current partitioning of your storage device, and the choices you make when creating space for the VMs, the device may be different than shown in the book. You’ll need to make adjustments for that as you perform the experiments pertaining to creation of the VMs.
- Page 472: Experiment 16-1, the file /boot/grub2/i386-pc/boot.img no longer exists due to changes in how GRUB uses the configuration files. Use the file /usr/lib/grub/i386-pc/boot.img here and in other places where the file /boot/grub2/i386-pc/boot.img is specified. This is the case on Page 473 also.
Volume 2
- Chapter 24 Special Filesystems, page 125, section Thrashing, second paragraph, “If you can manage to issue a command like free that shows CPU load and memory usage, …” The command free does not show CPU load. Thanks to Ivan Krajčer for letting me know about this error.
- Chapter 30, Automation with Ansible, Page 327, in Experiment 30-3, The ssh-keygen command now creates a public/private ed25519 key pair instead of the RSA pair that it previously did. This does not affect the results of this experiment or any of the following ones. Thanks to Ivan Krajčer for informing me of this change.
root@f42vm:~# ssh-keygen -b 2048
Generating public/private ed25519 key pair.
Enter file in which to save the key (/root/.ssh/id_ed25519):
Enter passphrase for "/root/.ssh/id_ed25519" (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_ed25519
Your public key has been saved in /root/.ssh/id_ed25519.pub
The key fingerprint is:
SHA256:F8AyZp5aTiocdwe7KDKN2NO9HTmUZyyGK1Rnktz1otI root@f42vm.both.org
The key's randomart image is:
+--[ED25519 256]--+
| . +... |
| @ =. . |
| = @ oo . |
| . o O.*.+o |
|.= = X.*E=. |
|= B * =.+. |
| o + . o o |
| . . |
| |
+----[SHA256]-----+
root@f42vm:~#
Volume 3
None at this time.