View source for DNS-server rhel7, sätta upp

== Sätta upp en DNS-server ==

Denna information är baserad på https://www.unixmen.com/setting-dns-server-centos-7/

Servern som DNS-servern installeras på har IP '''192.168.100.1/24''' och känner till en annan DNS-server med IP '''192.168.0.5'''.

=== Installera programvaran ===
 '''yum install bind bind-utils'''

=== Editera huvudkonfigurationsfil ===
Redigera filen '''/etc/named.conf''' och ändra det som är fetmarkerat nedan.
 //
 // named.conf
 //
 // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
 // server as a caching only nameserver (as a localhost DNS resolver only).
 //
 // See /usr/share/doc/bind*/sample/ for example named configuration files.
 //
 
 options {
     listen-on port 53 { 127.0.0.1; '''192.168.100.1;'''}; ### Master DNS IP ###
 '''#'''    listen-on-v6 port 53 { ::1; }; <- Denna rad kommenteras bort
     directory     "/var/named";
     dump-file     "/var/named/data/cache_dump.db";
     statistics-file "/var/named/data/named_stats.txt";
     memstatistics-file "/var/named/data/named_mem_stats.txt";
     allow-query     { localhost; '''192.168.100.0/24;'''}; ### IP Range ###
#     allow-transfer{ localhost; 192.168.1.102; };   ### Slave DNS IP ### <- Denna rad är bortkommenterad. Det finns ingen slavdns.
 
     /* 
      - If you are building an AUTHORITATIVE DNS server, do NOT enable recursion.
      - If you are building a RECURSIVE (caching) DNS server, you need to enable 
        recursion. 
      - If your recursive DNS server has a public IP address, you MUST enable access 
        control to limit queries to your legitimate users. Failing to do so will
        cause your server to become part of large scale DNS amplification 
        attacks. Implementing BCP38 within your network would greatly
        reduce such attack surface 
     */
     recursion yes;
 '''   forwarders {'''
 '''      192.168.0.5;''' <- Lokala namnservern på mitt nät
 '''    };'''
 
     dnssec-enable yes;
     dnssec-validation yes;
     dnssec-lookaside auto;
 
     /* Path to ISC DLV key */
     bindkeys-file "/etc/named.iscdlv.key";
 
     managed-keys-directory "/var/named/dynamic";
 
     pid-file "/run/named/named.pid";
     session-keyfile "/run/named/session.key";
 };
 
 logging {
         channel default_debug {
                 file "data/named.run";
                 severity dynamic;
         };
 };
 
 zone "." IN {
     type hint;
     file "named.ca";
 };
 
 '''zone "avdelning.net" IN {'''
 '''type master;'''
 '''file "forward.avdelning.net";'''
 '''allow-update { none; };'''
 '''};'''
 
 # Nedanstående kan hoppas över initialt
 '''zone "1.168.192.in-addr.arpa" IN {'''
 '''type master;'''
 '''file "reverse.unixmen";'''
 '''allow-update { none; };'''
 '''};'''
 
 include "/etc/named.rfc1912.zones";
 include "/etc/named.root.key";

=== Dags att konfigurera en zon-fil ===
Skapa '''/var/named/forward.avdelning.net''' med följande innehåll
 '''$TTL 86400'''
 
 '''@   IN   SOA    masterdns.avdelning.net. root.avdelning.net. ('''
 '''         2011071001  ;Serial'''
 '''         3600        ;Refresh'''
 '''         1800        ;Retry'''
 '''         604800      ;Expire'''
 '''         86400       ;Minimum TTL'''
 ''')'''
 '''@        IN   NS        masterdns.avdelning.net.'''
 '''@        IN   A         192.168.100.1'''
 '''masterdns     IN   A    192.168.100.1'''
 '''dhcpdns       IN   A    192.168.100.1'''

=== Aktivera och starta ===
Se till så DNS kan startas via systemctl
 '''systemctl enable named'''

Starta
 '''systemctl start named'''