Linux
Years of Linux notes: the command-line fixes, kernel and systemd quirks, performance tuning and server tricks I kept hitting and wrote down so I wouldn't forget them.
2025-12
2020-11
2020-07
2020-06
2020-05
2020-04
2020-01
2019-12
2019-11
2019-10
2019-02
2018-11
2018-10
2018-09
2018-03
2018-01
2017-10
2017-09
2017-08
2017-07
- Choose source IP with ping to force ARP refreshes
- Apache httpd 2.2.15-60: underscores in hostnames are now blocked
- mysqldump without table locks (MyISAM and InnoDB)
- Launching the cron.weekly forum
- Some more nuances to the systemd debacle
- Giving perspective on systemd’s “usernames that start with digit get root privileges”-bug
2017-05
2017-03
2017-02
2017-01
2016-08
2016-07
2016-05
2016-04
2016-03
2016-02
2016-01
- Coming soon: SysCast
- Delete files older than X days in Linux
- Sort ‘ps’ by memory usage in Linux
- Get the file or directory owner in Bash for use in scripts on Linux
- Apache 2.4 AH01762 & AH01760: failed to initialize shm (Shared Memory Segment)
- Introducing cron.weekly, a new weekly newsletter for Linux sysadmins
- Grep: show lines before and after the match in Linux
- apachectl on Linux: get the entire Apache vhost configuration in one output
2015-12
2015-11
2015-10
2015-09
2015-08
- MySQL Back-up: Take a mysqldump with each database in its own SQL File
- Install Go 1.5 On CentOS 6 and 7
- Effectively Using and Detecting The Slowloris HTTP DoS Tool
- Start or Stop a Service on CentOS 7
- Enable or Disable Service At Boot on CentOS 7
- Monitor All HTTP Requests (like TCPdump) On a Linux Server with httpry
- How To Use A Jumphost in your SSH Client Configurations
- supervisor job: spawnerr: can’t find command ‘something’
- Rsyslog Configuration with Dynamic Log File Destination Based On Program Name
- Logrotate On RHEL/CentOS 7 Complains About Insecure Permissions on Parent Directory, World Writable
- How To Increase Amount of Disk inodes in Linux
- How To Add Secondary IP / Alias On Network Interface in RHEL / CentOS 7
- Increase/Expand an XFS Filesystem in RHEL 7 / CentOS 7
2015-05
2015-04
2015-03
2015-02
2015-01
- Running a Tor relay: lessons learned
- My Fosdem 2015 Schedule
- Quick tests for GHOST gethostbyname () vulnerability (CVE-2015-0235)
- Modeling Package Manager Dependencies In Config Management
- GHOST: critical glibc update (CVE-2015-0235) in gethostbyname() calls
- Learning systemd
- Recent OpenSSL Security Advisories Are a Good Thing
- Flush all the content from Memcached via the CLI
2014-12
- Compiling from source faster: multi-threading in `make`
- MongoDB startup: /usr/bin/dirname: extra operand ‘2>&1.pid’
- Replacing Software Stacks Is Never The Solution
- List The Files In A Yum/RPM Package
- Generate PHP core dumps on segfaults in PHP-FPM
- Apache’s mod_fastcgi and mod_deflate troubles
- Puppet: could not prefetch yumrepo provider ‘inifile’: Section is already defined, cannot redefine
2014-11
- Devuan, the Debian Fork
- Rebuilding the yum RPM database
- Search yum for the content of a package
- Remote Code Execution via ‘less’ on Linux Boxes
- CPU Flame Graphs
- The PHP circle: from Apache to Nginx and back
- The Chocolatey Kickstarter: Making Windows More Like Linux
- Remove a single iptables rule
- Running Kali Linux as a Vagrant Box (virtual machine)
- Microsofts Open Source Strategy
2012-07
2012-06
- How to install and use the EPEL repository for CentOS 5 and CentOS 6
- Install VMware Tools via the Yum Package Manager on RHEL and CentOS
- Dependency errors for git installs on CentOS with EPEL repo
- Dependency fail on php-api when installing php-mcrypt or php-mhash from EPEL on CentOS 6
- How to change the reserved blocks on EXT3 or EXT4 filesystem in Linux
2012-05
2012-03
2012-02
- Xapian Bindings 1.2.7/8 in PHP: undefined symbol: zend_error_noreturn in Unknown on line
- SSH logins or rsync’s without using a password prompt
- Using ssh-copy-id on an alternative SSH destination port
- Incoming bandwidth limitation on OpenVZ with CentOS 6.x running on VMware ESX(i)
- Installing VMware Tools on a Debian 6 Linux Virtual Machine
- Checking the version of VMware Tools inside a Linux Virtual Machine on ESX(i)
- Removing a package without its dependencies in CentOS or RHEL
- On removing users with %postun in RPM SPEC files
- Changing interface back to eth0 from eth1 in Linux (CentOS/RHEL)
- Setting up a catch-all e-mail account on Linux using Postfix
- A vim configuration for the PHP developer
- Letting memcached only listen on localhost on CentOS/RHEL
- Enable syntax highlighting in VIM for PHP-FPM configurations
- The bugged sysinfo() call in OpenVZ hosts running Kernel 2.6.32+
- Add ‘Options FollowSymLinks’ and avoid ‘Options SymLinksIfOwnerMatch’ in Apache to save disk I/O
- Avoid ‘AllowOverride All’ in Apache to limit disk I/O access
- RHEL 6/ CentOS 6: Slow SSH logins with DNS timeouts
- The infamous /w00tw00t.at.ISC.SANS.DFind GET requests in your access logs
2011-12
2011-11
2011-08
2011-04
2011-03
2011-02
2010-12
2010-11
2010-09
2010-08
2010-01
2008-11
2008-10
- Limiting Resources: nice & ionice
- How To Mount A USB Hard Disk Through Command Line (Linux)
- Domains In Plesk Showing No Disk Usage Or Bandwidth
- Making The Switch To Linux – Keep In Mind … (10 Ubuntu Tips)
- Very Handy Linux CLI Cheat Sheet
- Plesk Issues After Upgrade (Horde Webmail Showing Default Plesk Page)
- How To Find Out Your Current Linux Distribution