Errata

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Last Updated on October 22, 2023 by David Both

This page contains errata for all of my Linux books. It does not contain lists of minor misspellings or inconsequential typographical errors. It does contain information about errors that result in significant inconsistencies, that may result in problems with the experiments, or that are incomplete or incorrect in the books. As many of these corrections as possible will be included in the next edition of these books.

If you do encounter any problems that you wish to bring to my attention, please contact me at LinuxGeek46@both.org and I will make any necessary corrections.

General Errata

2023-10-22: I have discovered that Thunar, the default file manager does, in fact, have the capability to display two directory panes side by side. I have erroneously written that it could not in multiple books and articles.

The Linux Philosophy for SysAdmins

  1. In Chapter 1, Page 9 (approximate Kindle location 831) The paragraph starting at the bottom of the page should read: “This book is not about learning new commands. Rather, it is about using the common and well-known commands with which you should already be familiar to illuminate the underlying structure of Linux at the command line. Think of this book and the commands you will use in the experiments like the X-rays, CT scans, and MRI’s that a doctor uses to reveal the inside of a human body. This book will show you how to use some simple Linux commands to reveal the underlying structure of GNU/Linux.”

Using and Administering Linux: 2nd Edition

None reported as of 2023-10-22.

Using and Administering Linux: 1st Edition

Using and Administering Linux: Additional information

This section of the errata contains information about some significant things that have changed since this series was first published.

Btrfs Filesystem

Fedora 33 became available in October 2020 and changes the default filesystem for new installations from the EXT4 filesystem to the BTRFS (B-Tree filesystem). Upgrades from to Fedora 33 from earlier releases maintain the existing EXT4 filesystems and do not change them.

Chapter 19 of Volume 1 of Using and Administering Linux discusses the EXT4 filesystem and Chapter 1 of Volume2 covers Logical Volume Management (LVM). This change to Btrfs as the default filesystem does not affect the accuracy of those chapters and they are still valid for EXT4 and LVM. Be sure to follow the directions in Chapter 5 of Volume 1 and use LVM for the partitioning scheme and select EXT4 for the filesystem types for all partitions except /boot.

The article, Choose between Btrfs and LVM-ext4, at Fedora Magazine has a short but good explanation of the similarities and differences between the two systems.

Download problems using wget

It was brought to my attention by reader Benjamin Robertson that experiments that use the wget command to download files from GItHub result in unusable files. This is due to an error in the URL and can easily be corrected.

For example, the command:

wget https://github.com/Apress/using-and-administering-linux-volume-2/blob/master/Experiment_6-1.txt

Should be:

wget https://github.com/Apress/using-and-administering-linux-volume-2/raw/master/Experiment_6-1.txt

Note that /blob/ should be changed to /raw/ in the above URL as well as others that use the wget command. The known instances of this problem are in:

  • Volume 1, Experiment 12-1
  • Volume 2, Experiment 6-1
  • Volume 2, Experiment 6-3
  • Volume 2, Experiment 17-1
  • Volume 3, Experiment 17-1

This problem does not occur when the wget command is used with other sites such as RPMFusion and WordPress. It only occurs with GitHub.

VirtualBox installation error

On page 79 of volume one trying to install virtual box but you may see the following error.

nothing provided python (abi) = 3.8 needed by virtualBox-6.1-6.1.18_142142_fedora32-1.x86_64.

This is a relatively new problem and can occur when some older Python libraries don’t get updated and get out of step with VirtualBox requirements. I have started using the “All distributions” (AMD) download which is at the bottom of the Linux distributions list of the VirtualBox Linux downloads page. This version seems to work well and has resolved the error shown above.

Thanks to “JJ” for bringing this to my attention.

Using and Administering Linux: Volume 1 – Zero to SysAdmin: Getting Started

  1. In Chapter 4, Preparation, Page 103, step 17 of creating the VM in a Linux environment, the change group (chgrp) command should be # chgrp vboxusers /Experiments/ which makes the group ownership of the /Experiments directory vboxusers instead of root. This prevents errors when attempting to create the virtual disk for StudentVM1. Thanks to Paolo Giuliani for bringing this error to my attention.
  2. The Btrfs filesystem is now the default for new installations. If you follow the directions in Chapter 5 for storage partitioning as shown in Figure 5-1, all of the experiments in all three volumes of this course will work as expected. You will just need to select LVM for the partitioning system.
  3. Figure 16-4, systemd targets on Page 472 has been revised to make the systemd targets the primary column and sorted in a manner that makes more sense for systemd.
  4. Experiment 16-4 has the student alter the /etc/defalt/grub configuration file to change the GRUB boot menu delay, and to remove rhgb and quiet from the kernel command line. It also has the student change the kernel variable GRUB_DISABLE_RECOVERY from true to false. This last change no longer causes each kernel to have a recovery boot option. The rest of this experiment works as it should regardless of the setting of this variable. This experiment is still valuable despite the fact that this one part no longer works as it once did.
  5. Figure 16-5 has rendered poorly in all the hardcopy and electronic versions. This image is correct and should render well.
  6. Figure 19-2 is incomplete. Check this revised version or download from my website, or from the Apress GitHub repository.

Using and Administering Linux: Volume 2 – Zero to SysAdmin: Advanced Topics

  1. In experiment 6-1, the download URL is incorrect. It should be github.com/Apress/using-and-administering-linux-volume-2/raw/master/Experiment_6-1.txt
  2. Chapter 12 in Volume 2 of my series “Using And Administering Linux,” needs some additional preparation. Due to some changes to the NetworkManager since this chapter was written in 2019, it is necessary to do a little preparation so that some experiments in Chapter 12 will work – specifically the experiments that relate to the interface configuration files. If you are using Fedora 36 or later, all that is necessary is to install one package that will provide support for the now deprecated interface configuration files. Run this command as the root user. [root@studentvm1 ~]# dnf -y install NetworkManager-initscripts-ifcfg-rh

Using and Administering Linux: Volume 3 – Zero to SysAdmin: Network Services

  1. In Chapter 2, the experiments still work and the nmcli commands do create the proper network interface configurations. The nmcli command now creates network keyfiles in the /etc/NetworkManager/system-connections directory. It no longer created network interface configuration files in the /etc/sysconfig/network-scripts directory. When you are instructed to look for the interface configuration files, look for the keyfiles in the /etc/NetworkManager/system-connections directory.
  2. There is an error in Figure 2-6. The interface and connection names should both be enp0s8. See the revised Figure 2-6.
  3. The nmcli command just under Figure 2-6 should be: [root@studentvm2 ~]# nmcli connection add save yes type ethernet ifname enp0s8 con-name enp0s8 ip4 192.168.56.1/24 This sets the IP address for the local virtual network on StudentVM2.
  4. The dig command in Experiment 2-4 contains an erroneous result. The Server line near the bottom of the output from that command should be ;; SERVER: 10.0.2.1#53(10.0.2.1)
  5. In Experiment 3-2, I have skipped an important step as was pointed out to me by a student in France. Add the following to the middle of Page 28 and replace the iplink command with it. “If StudentVM1 is running, power it off now. In the VirtualBox Manager, open the Settings dialog for StudentVM1. Go to the Network page and ensure that the Adapter 1 tab is selected. Set the Attached To: selection box to Host-only Adapter. This connects Adapter 1 to the new internal network we have created and removes it from the original network serviced by the virtual router. Start the StudentVM1 host. Nothing further will need to be done to obtain an IP address from the newly configured DHCP server. Login to StudentVM1, open a terminal session and su – to root. On StudentVM1, verify connectivity to the StudentVM2 server using the ping command. The -c option specifies the number of ping requests to send, in this case 2. We need to specify the IP address of the server because we do not yet have a name server on this network. [root@studentvm1 ~]# ping 192.168.56.1 -c2 “
  6. Experiment 4-5 starting on Page 51 contains some inconsistencies. The listing of the /etc/sysconfig/iptables file shows a rule to accept DNS requests on port 53 using only TCP. On Page 52, the result of the iptables-save command shows a rule that accepts DNS queries on UDP. In fact, IPTables should have rules for DNS port 53 for both UDP and TCP. This article explains.
  7. In Chapter 14, the installation and configuration procedure for TigerVNC has changed somewhere between Fedora 30 and 33. I am currently working on a revision to this procedure.