bind9-resolved-switch v1.2.1 [22 Sep 2024] - by Dominic
Description
A program to test whether bind9 (aka 'named') or systemd-resolved is the current active DNS resolver, and to switch permanently between them. Tested under Ubuntu 24.04 but should work on other recent systemd-based distros. It does not uninstall or break the alternative resolver, but sets up resolving so that the preferred resolver is used.
Before using bind9-resolved-switch.sh to switch to using bind9, you must first install bind9.
If run without options, bind9-resolved-switch.sh just shows the current DNS resolver.
bind9-resolved-switch.sh determines the current resolver based on /etc/resolv.conf, but there are 2 file changes it makes to enable bind9, or reverses to disable bind9:
1: /etc/resolv.conf - create static file with 'nameserver 127.0.0.1'
2: /etc/dhcp/dhclient.conf - add 'prepend domain-name-servers 127.0.0.1;'
Usage
./bind9-resolved-switch.sh [options]
Options
-b switch to using bind9 instead of systemd-resolved
-f proceed even if it seems unnecessary (but will still ask before making changes)
-h show this help and exit
-l show changelog and exit
-n hide program title
-r switch to using systemd-resolved instead of bind9
License
Copyright © 2024 Dominic Raferd. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0. Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
Changelog
1.2 [19 Jun 2024] - work with more recent versions of systemd which have resolvectl command instead of systemd-resolve, make shellcheck compliant
1.1 [11 Jun 2022] - small tweaks
1.0 [01 May 2020] - adapted from former program bind9-setup.sh
0.9 [26 Apr 2019] - add info to help about bind9-resolvconf
0.8 [26 Aug 2018] - fixes and improved text for -r and -s options
0.7 [21 Aug 2018] - add -s option
0.6 [21 Jul 2018] - add -r option, a few other fixes, still not fully tested
0.5 [27 Nov 2016] - fix bind not to use IPv6
0.4 [26 Nov 2016] - install bind from ubuntu repos instead of building
0.3 [17 Feb 2016] - build and attempt to install bind 9.10.3 (doesn't work unless bind already installed)
Download bind9-resolved-switch.sh
Donation
I have provided this software free gratis and for nothing. If you would like to thank me with a contribution, please let me know and I will send you a link. Thank you!
My Other Sites
- TimeDicer - Onsite/offsite data backup for Windows (uses rdiff-backup)
- Finding a 4D Backup Solution
- Web Scraping How To - extracting data from web sites
My Programs
Here is a selection of some (other) programs I have written, most of which run under GNU/Linux from the command line (CLI), are freely available and can be obtained by clicking on the links. Dependencies are shown and while in most cases written and tested on an x86-based Linux server, they should run on a Raspberry Pi, and many can run under Windows using Windows Subsystem for Linux (WSL) or Cygwin. Email me if you have problems or questions, or if you think I could help with a programming requirement.
Backup Utilities
- TimeDicer - Onsite/offsite data backup for Windows (uses rdiff-backup) [ GNU/Linux & MS Windows©: 2008-20 ]
- rdiff-backup-regress - GNU/Linux script to regress an rdiff-backup archive. [ GNU/Linux: 2012-24 ]
Debian/Ubuntu kernel and LVM Utilities
- kernel-remove - GNU/Linux script to list the installed GNU/Linux kernels in a Debian-based distro (e.g. Ubuntu), and can be used to remove an unwanted kernel and related packages, updating grub appropriately. [ GNU/Linux-Debian/Ubuntu: 2010-24 ]
- lvm-usage - GNU/Linux script to show available disk space and how it is used; run as cron job to warn if usage is above a set percentage. Provides additional information if LVM is in use. [ GNU/Linux: 2012-24 ]
- lvm-delete-snapshot - GNU/Linux script to remove LVM snapshot that has been left over by another process. [ GNU/Linux: 2012-21 ]
- netnames - GNU/Linux script shows current name, biosdevname and 'predictable name' of network device - helps with network device name scheme migration. [ GNU/Linux-Debian/Ubuntu: 2020-20 ]
- lv-convert2cache - GNU/Linux script to convert an existing LV into a cache LV using a smaller faster device as a cache. [ GNU/Linux: 2022-24 ]
Miscellaneous Programs
- sleepwalker - Windows© program which can be run from a remote machine to 'wake up' a Windows© machine behind a router, wait for it to start and then initiate Remote Desktop session. [MS Windows©: 2008-22]
- numliststat - GNU/Linux program giving statistical value(s) for a piped-in list of numbers. [ GNU/Linux: 2022-24 ]
- relay-enforcer - GNU/Linux program enabling a postfix-based mail server relaying to Gmail to act on reports from Gmail about blocked emails. [ GNU/Linux: 2016-24 ]
- pdf-compress - GNU/Linux program to create smaller b/w pdf file from an original large pdf file, especially when original resulted from scanning. [ GNU/Linux: 2016-23 ]
- tiny-device-monitor - GNU/Linux program to test webpages (including password-protected) or machines to check they are live; use as a cron job for your own websites, for hardware presenting a webpage, or for any machines with a presence on your local LAN or on the internet. [ GNU/Linux: 2009-24 ]
- form-extractor - GNU/Linux program to extract form tags from a web page or downloaded file. [ GNU/Linux: 2012-24 ]
- mythic-dns-sync - GNU/Linux program to update DNS record at mythic-beasts.com to match local external ip. [ GNU/Linux: 2016-23 ]
- saynoto0870 - For UK, a GNU/Linux script which performs automated lookup of the www.saynoto0870.com database, finding cheap or free geographic number replacements for expensive non-geographic (087* or 084*) numbers. [ GNU/Linux: 2012-12 ]
- unlock - GNU/Linux remote program for easy entering of decrypt passphrase on a remote machine which has root dm-crypt+LUKS. [ GNU/Linux: 2017-18 ]
- wifi-updown - GNU/Linux program to take down wifi interface if there is a working wired interface (or restore wifi if not). [ GNU/Linux: 2018-23 ]
- routefix - GNU/Linux program to restore a default ip traffic route if there is none such (e.g. after running wifi-updown). [ GNU/Linux: 2018-23 ]
- dutree - GNU/Linux program to show a tree-style list of files and directories at the specified location which are greater than the specified size (default 1GB). [ GNU/Linux: 2012-24 ]
- Accounts - Multi-business multi-currency accounting software, uses Access [MS Windows©: 1996-2024]
- Rents Program - Residential lettings/landlord front office program, with many special features for UK market [MS Windows©: 1991-2024]
This section is closed. If you have a question, please submit it by email, thank you.