System monitoring from the command line
Command Line – watch and fswatch
© Lead Image © Shao-Chun Wang, 123RF.com
Two monitoring tools, watch and fswatch, let you gather system information from the command line.
Most users familiar with Linux have probably used cron or at to schedule the running of commands. Both can be useful in their place: cron for repeated scheduling of events and at for scheduling an event once. However, what both lack is the ability to gather system information and respond to it unless you write a specific script. Usually, it is much easier to use watch [1] and fswatch [2] to do both these things. While watch and fswatch can be used simply to gather information or to check for possible security incursions, both can be tweaked to act like a scheduler with little effort and minimal script-writing ability.
watch
The purpose of watch is to follow how a command's output changes over time (Figure 1). This information can be used for troubleshooting, as well as for keeping a root or regular user informed about system changes as new packages are installed or updated. In limited circumstances, it could also be used as a simpler replacement for at or cron. Several other common uses are shown in Table 1. By default, watch runs every two seconds until closed or interrupted. The basic command structure is:
watch OPTIONS COMMAND
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
TuxCare Announces Support for AlmaLinux 9.2
Thanks to TuxCare, AlmaLinux 9.2 (and soon version 9.6) now enjoys years of ongoing patching and compliance.
-
Go-Based Botnet Attacking IoT Devices
Using an SSH credential brute-force attack, the Go-based PumaBot is exploiting IoT devices everywhere.
-
Plasma 6.5 Promises Better Memory Optimization
With the stable Plasma 6.4 on the horizon, KDE has a few new tricks up its sleeve for Plasma 6.5.
-
KaOS 2025.05 Officially Qt5 Free
If you're a fan of independent Linux distributions, the team behind KaOS is proud to announce the latest iteration that includes kernel 6.14 and KDE's Plasma 6.3.5.
-
Linux Kernel 6.15 Now Available
The latest Linux kernel is now available with several new features/improvements and the usual bug fixes.
-
Microsoft Makes Surprising WSL Announcement
In a move that might surprise some users, Microsoft has made Windows Subsystem for Linux open source.
-
Red Hat Releases RHEL 10 Early
Red Hat quietly rolled out the official release of RHEL 10.0 a bit early.
-
openSUSE Joins End of 10
openSUSE has decided to not only join the End of 10 movement but it also will no longer support the Deepin Desktop Environment.
-
New Version of Flatpak Released
Flatpak 1.16.1 is now available as the latest, stable version with various improvements.
-
IBM Announces Powerhouse Linux Server
IBM has unleashed a seriously powerful Linux server with the LinuxONE Emperor 5.