Linux named / bind how to dump, view and clear the cache!

Do you hate it when your ISP has old cached records because of a high TTL on the DNS record of the relevant domain?  In plain English this means you often can't connect to a site or service because your ISP's DNS servers haven't gotten word of the new IP address (probably because they haven't checked).  There are also some that are notorious for ignoring TTL and not updating records for days!

But if you are lucky and smart enough to have your own Linux based DNS server you can do the following:

rndc dumpdb -cache

This let's you see the cached entries by writing the bind cache to /var/named/data/cache_dump.db

If you just want to clear your DNS cache:

rndc flush

The above flushes all of your DNS cache which is never a bad idea since it saves memory and increases the performance potentially.


Tags:

linux, bind, cache, isp, cached, ttl, dns, relevant, domain, servers, haven, ip, notorious, ignoring, updating, server, rndc, dumpdb, entries, var, cache_dump, db, rdnc, flush, flushes, saves, increases, potentially,

Latest Articles

  • how to use ifplugd in Linux to execute a command or script when a NIC cable is unplugged or plugged in
  • dd how to backup and restore disk images including compression with gzip
  • mpv / mplayer with Radeon / AMD GPU Video Card Driver enable VDPAU GPU Accelerated Video Decoding
  • Wordpress Reset Blog User Password from MySQL Using Linux Bash and not PHPMyadmin
  • Ubuntu Linux Mint Debian xorg performance and tear-free tuning for AMD Radeon Based Cards
  • Centos 7 Stopped and Disabled Firewalld and ports still blocked
  • MariaDB / MySQL Reset Root Forgotten Password on Centos 7
  • Centos 7 How to install Mysql/Mariadb
  • PHP 7.2, Apache and Centos 7 How To Install
  • Ubuntu Debian Linux Mint r8169 r8168 Network Driver Problem and Solution
  • Linux 3D Performance benchmarks with glxgears 59-60fps solution
  • How To Install Asterisk 16 17 on Debian Ubuntu Linux
  • Linux Ubuntu Debian Centos How To Make a Bootable Windows 7, 8, 10, 2016, 2019 Server USB from ISO
  • How To Restore Windows MBR Bootsector from Linux using syslinux
  • Linux Ubuntu Cannot Print Large Images
  • Cannot Print PDF Solution and Howto Resize
  • Linux Console Login Screen TTY Change Message
  • Apache Cannot Start Listening Already on 0.0.0.0
  • MySQL Bash Query to pipe input directly without using heredoc trick
  • CentOS 6 and 7 / RHEL Persistent DHCP Solution