Linux 8: Setup DNS for Grid 19c Setup on VirtualBox

 # Public network

192.168.56.110   rac1.example.com  rac1

192.168.56.111   rac2.example.com  rac2

# Virtual IPs

192.168.56.121   rac1-vip.example.com  rac1-vip

192.168.56.122   rac2-vip.example.com  rac2-vip

# SCAN IPs

192.168.56.131   scan-ls.example.com   scan-ls

192.168.56.132   scan-ls.example.com   scan-ls

192.168.56.133   scan-ls.example.com   scan-ls

# Private interconnect (optional)

192.168.10.1   rac1-priv

192.168.10.2   rac2-priv

yum install -y bind bind-utils

/etc/named.conf

options {

    directory "/var/named";

    listen-on port 53 { 127.0.0.1; 192.168.56.110; };

    allow-query { 127.0.0.1; 192.168.56.0/24; 192.168.10.0/24; };

    recursion yes;

    // Lab simplifications

    dnssec-enable no;

    dnssec-validation no;

    auth-nxdomain no;

};

zone "example.com" IN {

    type master;

    file "db.example.com";

};

zone "56.168.192.in-addr.arpa" IN {

    type master;

    file "db.192.168.56";

};

zone "10.168.192.in-addr.arpa" IN {

    type master;

    file "db.192.168.10";

};

 mkdir /var/named/

 /var/named/db.example.com

$TTL 86400

@   IN  SOA  rac1.example.com. root.example.com. (

        2025100801 ; Serial (bump on edits)

        3600       ; Refresh

        1800       ; Retry

        604800     ; Expire

        86400 )    ; Minimum

@           IN  NS  rac1.example.com.

; DNS server itself

rac1        IN  A   192.168.56.110

; Public hosts

rac2        IN  A   192.168.56.111

; VIPs

rac1-vip    IN  A   192.168.56.121

rac2-vip    IN  A   192.168.56.122

; SCAN (must have 3 A records)

scan-ls     IN  A   192.168.56.131

scan-ls     IN  A   192.168.56.132

scan-ls     IN  A   192.168.56.133

; Private (optional)

rac1-priv   IN  A   192.168.10.1

rac2-priv   IN  A   192.168.10.2

/var/named/db.192.168.56

$TTL 86400

@   IN  SOA  rac1.example.com. root.example.com. (

        2025100801

        3600

        1800

        604800

        86400 )

@           IN  NS  rac1.example.com.

110 IN PTR rac1.example.com.

111 IN PTR rac2.example.com.

121 IN PTR rac1-vip.example.com.

122 IN PTR rac2-vip.example.com.

131 IN PTR scan-ls.example.com.

132 IN PTR scan-ls.example.com.

133 IN PTR scan-ls.example.com.

/var/named/db.192.168.10

$TTL 86400

@   IN  SOA  rac1.example.com. root.example.com. (

        2025100801

        3600

        1800

        604800

        86400 )

@           IN  NS  rac1.example.com.

1   IN PTR rac1-priv.example.com.

2   IN PTR rac2-priv.example.com.

chown root:named /var/named/db.example.com /var/named/db.192.168.56 /var/named/db.192.168.10

chmod 640 /var/named/db.*

named-checkconf

named-checkzone example.com /var/named/db.example.com

named-checkzone 56.168.192.in-addr.arpa /var/named/db.192.168.56

named-checkzone 10.168.192.in-addr.arpa /var/named/db.192.168.10

systemctl enable --now named

systemctl status named --no-pager