Articles in Category "Administration"

Providing XDG Runtime Directories

Introduction The intended audience for this document are application programmers and providers of init-systems for managing features of installations of the GNU/Linux operating system and POSIX-compliant operating systems in general, who are concerned with per-user temporary file management based on the XDG Base Directory Specification, [XDG]. Many applications that follow XDG guidelines and specifications expect […]

Ad-Blocking with BIND9 and NGINX

In my intranet, where hosts are in a subnet 192.168.2.0/24 and domain names in a domain mydomain, I use BIND9 as DNS, running on host intradns.mydomain , and NGINX as a webserver running on intraweb.mydomain. I would like to rewrite all subdomains of certain public domains (spammers and trackers) using my intranet DNS to a […]

RDP With Copy&Paste From Windows to xrdp on Debian

The package of xrdp (Version 6.1.2) that is available in Debian does lack support for Copy&Paste. The „master“ branch of xrdp on github provides this feature but is not packaged for Debian at the moment. To have it available, I built it manually on my Debian server. The procedure took about 1 hour, most of […]

Ubuntu 14.10 cryptswap1 With LVM Stops Working After Reboot

Today I rebooted an Ubuntu 14.10 that was set up with LVM and encryption. It was unable to use the encrypted swapspace cryptswap1, which ultimately halted the boot procedure with a prompt (S for skip and M for manual resolution, i.e. single-user-mode prompt). The problem appears to be that the UUID (blkid) of the designated […]

Filtering and Rate-Limiting ICMPv6 on a GNU/Linux Server

Introduction ICMP (Internet Control Message Protocol) in IPv6 is used for a variety of purposes. As opposed to IPv4, support for some of the applications of ICMP by nodes participating in an IPV6 network is mandatory. On the other hand, due to the security-relvant nature of some of the applications, where in IPv4 it may […]

Using VIm’s „:v“ to Delete All Lines NOT Containing a Pattern

Addendum to my previous post „Using VIm’s „Negative Lookahead“ to Delete All Lines NOT Containing a Pattern„ I received a message from a reader who goes by the name of „bw1“ who points out that my task „to delete all lines in the current file not containing the string foo“ can easily be accomplished by […]

Text-Console Barchart of Storage Utilization

Written as a Bourne Shell-Script that invokes a Perl one-liner: LC_ALL=C df -kPT | perl -ane ‚!/(^Filesystem|tmpfs)/ && do { printf(„%-33s: %s\n“, $F[0], „*“ x int((`tput cols`-35) * $F[3] / $F[2])) }‘  

Using VIm’s „Negative Lookahead“ to Delete All Lines NOT Containing a Pattern

UPDATE: Please note that „bw1“ has notified me of a much simpler solution than what is described here; please see „Using VIm’s „:v“ Command to Delete All Lines NOT Containing a Pattern„ Some statements have been struck through in the article below because they are false. I want to delete all lines in the current […]