Blogpost archive
This is a list of all my blogposts. They range from highly technical to entry level, from Linux to PHP and server management.
If you have an interesting topic to write about, reach out and I'll see what I can do.
2016-04
2016-03
- Running Bash on Ubuntu on Windows: Demo
- Ruby gem search: show all remote versions
- nginx-1.9.13: no longer retry non-idempotent upstream requests by default
- certdiff
- Postfix: cannot update mailbox /var/mail for user, File too large
- Optimize the size of .PNG images automatically on your webserver with optipng
- PHP Warning: Zend OPcache can’t be temporary enabled
- Mac OSX: mtr: unable to get raw sockets
- Example: set an advanced parameter value in VMware via vSphere PowerCLI
- Pre-compress content for Apache to avoid compressing on every request
- Set Access-Control-Allow-Origin (CORS) headers in Apache vhost or htaccess
- The “.well-known” directory on webservers (aka: RFC 5785)
- Remote Code Execution in all git versions (client + server) < 2.7.4: CVE-2016-2324, CVE-2016‑2315
- Drupal’s itok parameters explained and a Varnish workaround for different backends
- Nginx Proxy: upstream sent too big header while reading response header from upstream
- A technical guide to SEO
- OpenSSL vulnerabilities: DROWN attack and CacheBleed
2016-02
2016-01
- A clean mailing list browser, focussing on readability
- 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
- Review: Google Chromecast 2
- The best tech question to ask in a job interview
- Grep: show lines before and after the match in Linux
- apachectl on Linux: get the entire Apache vhost configuration in one output
- PHP-FPM: failed to ptrace(PEEKDATA) pid 123: Input/output error (5)
2015-12
- Podcast: Delving into HTTP/2
- Use awk to filter log files on values ‘greater than’ or ‘less than’ a threshold in Linux
- PHP pear.php.net is using a unsupported protocol – This should never happen.
- PHP Composer installation fails: file could not be downloaded: allow_url_fopen must be enabled
- Drush PEAR channel: Error getting channel info from pear.drush.org
- Linux Date Format: change the date output for scripts or commands
- Very simple ‘git push’ workflow to deploy code on your own server
- Identify a physical NIC from the Linux CLI with ‘ethtool’
- PHP Session Locking: How To Prevent Sessions Blocking in PHP requests
- MySQL: Convert a table from MyISAM to InnoDB or vica versa
- How to set iTerm2 as the default ssh:// handler on Mac OSX
2015-11
- What is a ‘unikernel’?
- Querying JSON data at the command line with ‘jq’
- PHP’s Memcached sessions: Failed to write session data (memcached) for Magento
- Create a password-protected ZIP file on Mac OSX
- Chrome drops NPN support for HTTP/2, ALPN only
- Simulate low-bandwidth conditions with Chrome’s network throttling
- Auto resize screen size for Windows 10 guest VMs in Virtualbox
- Nginx: Cannot assign requested address for upstream
- Linux increase ip_local_port_range TCP port range
2015-10
- Enable Keepalive connections in Nginx Upstream proxy configurations
- The Lie We Live: The Gigabyte That Isn’t
- Varnish VCL Syntax Highlighting in Sublime Text
- How To Generate a /etc/passwd password hash via the Command Line on Linux
- Firefox Nightly starts marking login-forms in HTTP as insecure
- A Distributed Web
- 25% of all websites are about to get a REST API
- The Ping That Makes a Sound
2015-09
2015-08
- Pretty git log in one line
- MySQL Back-up: Take a mysqldump with each database in its own SQL File
- Install Go 1.5 On CentOS 6 and 7
- Foreman 1.9: ERROR: column hosts.last_freshcheck does not exist
- Apache 2.4: Unknown Authz provider: ip
- iPhone’s “Field Test” debug screen: Dial *3001#12345#* for the real signal strength
- Nginx SSL Certificate Errors: PEM_read_bio_X509_AUX, PEM_read_bio_X509, SSL_CTX_use_PrivateKey_file
- The Hidden “Refresh” Menu in Chrome when Developer Tools Are Opened
- Apple’s DYLD_PRINT_TO_FILE vulnerability: from zero to root in 2 seconds
- Bind/Named Crash: REQUIRE(*name == ((void *)0)) failed, CVE-2015-5477
- How To Read The SSL Certificate Info From the CLI
- What happens to a new URL the first 10 minutes on the internet?
- Block User-Agent in htaccess for Apache Webserver
- 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
- How To Create A Self-Signed SSL Certificate With OpenSSL
- supervisor job: spawnerr: can’t find command ‘something’
- How To Clear PHP’s Opcache
- How To Take a Screenshot on Your Apple Watch
- 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
- Apache 2.4: ProxyPass (For PHP) Taking Precedence Over Files/FilesMatch In Htaccess