The sys admin's daily grind – Pdnsd
Short-Term Memory
Cache it, if you can! When the latencies of his Internet connection seem to take longer than Napoleon's reign, sys admin Charly comes up with a solution for name resolution.
It is always annoying when I need to use Internet via a satellite route. The latency is really bad. To counteract this, I use caching wherever I can. My choice of cache for DNS requests is Pdnsd [1]. More or less any fat distribution will have the lean and fast daemon in its collection. When launched, the daemon parses the content of /etc/hosts
and stores it in its cache. Any DNS requests that I make are added.
By default, the cache is 2MB. If you have built a very long /etc/hosts
throughout your IT landscape, you can modify the cache size in /etc/pdnsd.conf
. The matching option resides in the global
section. It goes by the name of perm_cache
and expects the size in bytes – I use 8192
. By the way, the option is named perm_cache
because the cache not only resides in RAM but also on the disk. In other words, Pdnsd does not need to build the cache from scratch after a reboot.
In the global
configuration section, you will find other central settings. One setting that is very important is:
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
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
-
AUR Repository Still Under DDoS Attack
Arch User Repository continues to be under a DDoS attack that has been going on for two weeks.
-
RingReaper Malware Poses Danger to Linux Systems
A new kind of malware exploits modern Linux kernels for I/O operations.
-
Happy Birthday, Linux
On August 25, Linux officially turns 34.
-
VirtualBox 7.2 Has Arrived
With early support for Linux kernel 6.17 and other new additions, VirtualBox 7.2 is a must-update for users.
-
Linux Mint 22.2 Beta Available for Testing
Some interesting new additions and improvements are coming to Linux Mint. Check out the Linux Mint 22.2 Beta to give it a test run.
-
Debian 13.0 Officially Released
After two years of development, the latest iteration of Debian is now available with plenty of under-the-hood improvements.
-
Upcoming Changes for MXLinux
MXLinux 25 has plenty in store to please all types of users.
-
A New Linux AI Assistant in Town
Newelle, a Linux AI assistant, works with different LLMs and includes document parsing and profiles.
-
Linux Kernel 6.16 Released with Minor Fixes
The latest Linux kernel doesn't really include any big-ticket features, just a lot of lines of code.
-
EU Sovereign Tech Fund Gains Traction
OpenForum Europe recently released a report regarding a sovereign tech fund with backing from several significant entities.