Table of Contents

Middleware

BIND (named)

Reference


Commands

Checking

Operation Commands
checking configuration /etc/init.d/named configtest
checking named.conf named-checkconf
named-checkconf /etc/named.conf
checking grammar named-checkzone ZONE_NAME FILE
named-checkzone example.com /var/named/named.example.com
named-checkzone 10.in-addr.arpa /var/named/named.rev


Update Zone Configuration

Update All Zone Contents rndc reload
Update example.com Zone Contents rndc reload example.com
add new zone file rndc reconfig


Cash Clear

In DNS Server
if you are not collect a name resolution, you use rndc command.
rndc flushname SERVER1
rndc flushname SERVER1.EXAMPLE.COM
In DNS Server/Client Host
if you are useing nscd, you use nscd command.
nscd -i hosts


How to check TTL.

[user01@centos7 ~]$ dig google.com | grep ^google.com
google.com.             287     IN      A       172.217.26.46
[user01@centos7 ~]$ 
[user01@centos7 ~]$ 
[user01@centos7 ~]$ dig google.com | grep ^google.com
google.com.             285     IN      A       172.217.26.46
[user01@centos7 ~]$ 
[user01@centos7 ~]$ dig google.com | grep ^google.com
google.com.             284     IN      A       172.217.26.46
[user01@centos7 ~]$ 
[user01@centos7 ~]$ while : ; do  echo -n "`date ` : " ; dig google.com | grep ^google.com ; sleep 1 ; done
Wed May 24 20:12:16 JST 2017 : google.com.              164     IN      A       172.217.26.46
Wed May 24 20:12:17 JST 2017 : google.com.              163     IN      A       172.217.26.46
Wed May 24 20:12:18 JST 2017 : google.com.              161     IN      A       172.217.26.46
Wed May 24 20:12:19 JST 2017 : google.com.              160     IN      A       172.217.26.46
Wed May 24 20:12:20 JST 2017 : google.com.              159     IN      A       172.217.26.46
Wed May 24 20:12:21 JST 2017 : google.com.              158     IN      A       172.217.26.46
^C