today's howtos

posted by Roy Schestowitz on Jul 12, 2023

• Monitoring System Metrics With Grafana and Prometheus

  Monitoring system metrics provides insights into how a system is performing and can help identify issues that may impact system availability, user experience, and overall system health. By monitoring metrics such as CPU usage, memory usage, disk utilization, network traffic, and other critical parameters, you can proactively identify and resolve issues before they become significant problems.

  In this article, you’ll learn how to set up a monitoring stack consisting of Grafana, Prometheus, Alertmanager, and Node-exporter using Docker-compose. By the end of this tutorial, you will have a fully functional monitoring system that can help you keep track of your system’s performance and identify any issues that may arise.

• Notes on Linux's /proc/locks and NFS v4 locks as of Ubuntu 22.04

  Unlike the situation with NFS v3 locks, where you have to dig into the kernel data structures to find the client who owns a lock, it appears that the NFS v4 server directly exposes this information in files under /proc/fs/nfsd. Based on casual inspection, 'clients/<id;>/states' appears to contain information on delegations and locks from that client, while 'clients/<id>/info' identifies the client. Actual locks in the 'states' file are 'type: lock', as opposed to the other types (which may appear in quantity, due to delegations).

• How I move URLs between browsers in my Unix desktop environment

  For my desktop environment, I use fvwm with a completely custom setup (this old entry on my desktop is still pretty accurate MyDesktop). These days my multiple browsers are actually Firefox profiles, so I have a cover script to run Firefox with my 'JavaScript enabled' profile and whatever remaining command line options; this is more or less 'firefox -P Javascript "$@"' (although in practice I always use it with --new-window, because for browser organization I usually prefer windows over tabs).

• Backing Up and Archiving to Removable Media: dar vs. git-annex

  This is the fourth in a series about archiving to removable media (optical discs such as BD-Rs and DVD+Rs or portable hard drives). Here are the first three parts: [...]

• The day my ping took countermeasures

  At this point we could conclude our investigation. We're now able to reliably trigger the "taking countermeasures" message using strace fault injection.

  There is one more thing though. When sending ICMP Echo Request messages, does ping remember the send timestamp in some kind of hash table? That might be wasteful considering a long-running ping sending thousands of packets.

  Ping is smart, and instead puts the timestamp in the ICMP Echo Request packet payload!

  Here's how the full algorithm works: [...]

• How to Install PHP 8 on RHEL 9 | Rocky Linux 9 | AlmaLinux 9

• Fd: The Find Command Alternative For Mastering File Search In Linux

  When it comes to managing files on a computer, finding specific files or directories quickly and efficiently can be a common task. Whether you're a developer looking for a specific code file, a system administrator searching for log files, or a regular user trying to locate a document, having a reliable and user-friendly file search tool can greatly simplify the process. One such tool that has gained popularity among Linux users is "fd". Designed as a user-friendly alternative to the traditional find command, fd provides a more intuitive and efficient method for searching files and directories. In this detailed tutorial, we will discuss what is fd, key differences between the fd and find command. We will also learn how to install and use fd command to efficiently search files and directories in Linux.