This post summarizes new features, bugfixes and changes in Linux kernel release 4.19.70. Linux 4.19.70 Release contains 95 changes, patches or new features. In total, there are 101,521 lines of Linux source code changed/added in Linux 4.19.70 release compared to Linux 4.19 release. To view the source code of Linux 4.19.70 kernel release online, please
Read more
Tag: systemd
How to Install Hyperledger Fabric 2.0 in Ubuntu 18.04
Posted onHyperledger Fabric is a consortium blockchain system. It’s performance is relatively good and its modular architecture enables it to be usable in many scenarios. Hyperledger Fabric itself has rich documents and samples of test networks. For beginners, deploying a new network for trying and testing still consumes quite some time. In this post, we will
Read more
How to force a fsck during next rebooting of Linux?
Posted onHow to force a fsck of a file system, say the root, during the next rebooting of Linux? 2 possible ways: /forcefsck way for / # touch /forcefsck and reboot. Next time the / will be fsck’ed . systemd way Add these 2 kernel boot parameters: fsck.mode=force fsck.repair=yes What these 2 kernel parameters do: KERNEL
Read more
How to make CentOS Linux to load a module automatically at boot time?
Posted onHow to make CentOS Linux to load a module, say ixgbe, automatically at boot time? I am using CentOS 7. You can create a text file <some name>.conf in the /etc/modules-load.d/ and list the modules to be loaded there, one per line. The systemd-modules-load.service daemon will read these files and load the modules. Check more
Read more
How to force systemd to refresh or reloaded a changed fstab on Linux?
Posted onOn Linux, how to force systemd to refresh or reloaded a changed /etc/fstab file? To force systemd to reload the changed /etc/fstab file content, run $ sudo systemctl daemon-reload To, further, make systemd auto remount any new entries, do $ sudo systemctl restart remote-fs.target local-fs.target
How to check last boot’s systemd journal log in CentOS 7 Linux?
Posted onThe command to check last boot’s journal log shows nothing on CentOS 7: # journalctl -b -1 Failed to look up boot -1: No such boot ID in journal Is the log stored and where it is? The reason this happens on CentOS 7 is that CentOS 7 by default does not enable the persistent
Read more
How to make Ubuntu Linux boot to text mode?
Posted onMy Ubuntu boots to GUI mode by default. How to make Ubuntu Linux boot to text mode? If you are using Ubuntu older than 16 such as Ubuntu 14.04: Edit /etc/default/grub Change GRUB_CMDLINE_LINUX=… to GRUB_CMDLINE_LINUX=”text”. Backup your old grub config`$ sudo cp -n /etc/default/grub /etc/default/grub.bak-date +%s ` Update grub$ sudo update-grub If you are using
Read more
How to make the rpcbind.service auto start in systemd on Linux?
Posted onThe command systemctl enable rpcbind.service seems not work. The rpcbind.service does not start after rebooting. How to make/force the rpcbind.service auto start in systemd on Linux? You an force the rpcbind.service to start by making it be “wanted” by the target such as multi-user: # systemctl add-wants multi-user rpcbind.service This will force rpcbind.service to start.
How to make journalctl faster?
Posted onOn Linux, I check system logs by journalctl. But it is soooo slow. How to make it faster. By default without any options, the journalctl is indeed very slow. But usually, we are only interested in some logs and can use options to specify the logs that we are interested to check. This will make
Read more
How to change the display manager on Fedora Linux?
Posted onThe default display manager on my Fedora 22 is gdm. If I would like to change it to other display manager like KDM, LightDM or other, which is the portable and reliable method? You can use the “system-switch-displaymanager” tools to manage the display manager. This is possibly the most portable way. To install it: #
Read more
How to make Fedora Linux not clean some files in /tmp/?
Posted onOn my Fedora 20, I find that the system automatically clean up file under /tmp/. This is convenient. However, it cause some problems for some programs. For example, HDFS puts its DataNode pid file under /tmp/ by default like hadoop-hadoop-datanode.pid. After it is cleaned up, the hadoop-daemon.sh script will consider there is no DataNode running.
Read more
How to configure systemd to boot Linux to console mode (runlevel 3)?
Posted onHow to configure Linux (am using Fedora 21) managed by systemd to boot to console (init 3) mode? systemd has the concept of targets as a more flexible replacement for runlevels in sysvinit. Runlevel 3 is emulated by multi-user.target. runlevel3.target is a symbolic link to multi-user.target. You can switch to ‘runlevel 3’ by running #
Read more
How to exclude last N columns in Bash on Linux?
Posted onHow to exclude last N columns of a string in bash? The point is that the number of columns in each line is uncertain (but > N). For example, I would like to remove the last 2 columns separated by ‘.’ in the following lines. systemd.3.gz systemd.mount.3.gz systemd.mount.f.3.gz The simple cut command cut -d’.’ -f1
Read more
How to disable the coredump function of systemd on Linux?
Posted onI do not want to have coredump for the developing machine using systemd on Linux? How to disable the coredump function of systemd? You can disable coredump function of systemd by adding this line Storage=none to /etc/systemd/coredump.conf For your reference: Storage= Controls where to store cores. One of “none”, “external”, “journal”, and “both”. When “none”,
Read more
How to replace gdm with lightdm on Fedora
Posted onCinnamon does not work well with gdm. And there is no meaning to use gdm when using Cinnamon. On Fedora, the default one id gdm. How to replace gdm with lightdm on Fedora? First, install lightdm if it is not installed yet: # yum install lightdm lightdm-gtk Then, disable gdm service and make the lightdm
Read more
Changing Systemd Boot Target in Linux
Posted onMany Linux distros, such as RHEL/CentOS 7, Fedora, Ubuntu 16, are now using systemd instead of init as the init system. It is common for Linux users to set Linux to boot to “GUI” or “Text” mode. The old way of changing ‘/etc/inittab’ for choosing Linux runlevels is not working for sytemd. This post will
Read more
Controlling Filesystem Mounting on Linux using /etc/fstab
Posted onControlling the mounting of filesystems is a useful technique for managing Linux systems. The mounting configurations are mostly in the /etc/fstab file. In this post, we will discuss 2 common and useful techniques for controlling the filesystem mounting by playing with the /etc/fstab file: allowing non-root users to mount/unmount filesystems and avoiding mounting failures blocking
Read more
How to Change Systemd Runlevel on Fedora Linux – The Manual Way
Posted onFedora Linux starts to use systemd to manage system service. The /etc/inittab is no longer used by systemd. The old method of editing /etc/inittab to change system runlevel does not work anymore. This post introduces a “manual” way to change the boot levels. For the general method, please check https://www.systutorials.com/change-systemd-boot-target-linux/. systemd uses ‘targets’ instead of
Read more