How to boot into command line on Ubuntu or Debian

Question: I am running Ubuntu desktop, but I want to boot straight into text-mode console temporarily. What is a convenient way to disable desktop GUI and boot into a terminal? Linux desktop comes with a display manager (e.g., GDM, KDM, LightDM), which lets the desktop machine automatically boot into a GUI-based login environment. However, what […]
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How to find information about built-in kernel modules on Linux

Question: I would like to know what modules are built into the kernel of my Linux system, and what parameters are available in each module. Is there a way to get a list of all built-in kernel modules and device drivers, and find detailed information about them? The modern Linux kernel has been growing significantly […]
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How to find out which CPU core a process is running on

Question: I have a Linux process running on my multi-core processor system. How can I find out which CPU core the process is running on? When you run performance-critical HPC applications or network-heavy workload on multi-core NUMA processors, CPU/memory affinity is one important factor to consider to maximize their performance. Scheduling closely related processes on […]
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How to remove unused old kernel images on Ubuntu

Question: I have upgraded the kernel on my Ubuntu many times in the past. Now I would like to uninstall unused old kernel images to save some disk space. What is the easiest way to uninstall earlier versions of the Linux kernel on Ubuntu? In Ubuntu environment, there are several ways for the kernel to […]
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How to view threads of a process on Linux

Question: My program creates and executes multiple threads in it. How can I monitor individual threads of the program once they are created? I would like to see the details (e.g., CPU/memory usage) of individual threads with their names. Threads are a popular programming abstraction for parallel execution on modern operating systems. When threads are […]
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How to compile ixgbe driver on CentOS, RHEL or Fedora

Question: I want to build and install the latest ixgbe 10G NIC driver. How can I compile ixgbe driver on CentOS, Fedora or RHEL? To use Intel’s PCI Express 10G NICs (e.g., 82598, 82599, x540) on your Linux system, you need to install ixgbe driver. While modern Linux distributions come with ixgbe driver pre-installed as […]
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How to install full kernel source on Debian or Ubuntu

Question: I need to download and install a full kernel source tree to compile a custom kernel for my Debian or Ubuntu system. What is a proper way to download full kernel source on Debian or Ubuntu? Before installing full kernel source on your Linux system, ask yourself whether you really need the full kernel […]
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How to download and install ixgbe driver on Ubuntu or Debian

Question: I want to download and install the latest ixgbe driver for my Intel 10 Gigabit Ethernet card. How can I install ixgbe driver on Ubuntu (or Debian)? Intel’s PCI Express 10 Gigabit (10G) network inerface cards (e.g., 82598, 82599, x540) are supported by ixgbe driver. The stock kernel of the modern Linux distributions already […]
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How to install kernel headers on Linux

Question: I need to install kernel headers to install a device driver for my kernel. What is a proper way to install matching kernel headers on [insert your Linux distro]? When you compile a device driver a custom kernel module, you need to have kernel header files installed on your Linux system. Kernel headers are […]
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How to reset RX/TX counters of a network interface

Question: I am testing a network interface card (NIC), and currently ifconfig command reports huge numbers on RX/TX and error/dropped counters on some interface. Is there a way to reset ifconfig packet counters on a network interface without rebooting the server? On Linux, each network interface comes with several packet counters such as RX (number […]
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