ĂversĂ€ttningen av artikeln förbereddes för studenter i kursen . Ăr du intresserad av att utvecklas inom detta omrĂ„de? Titta pĂ„ inspelningen av Ivan Piskunovs mĂ€sterklass.
I den hÀr artikeln kommer jag att berÀtta om stegen för att konfigurera en DNS-server pÄ RHEL 7 eller CentOS 7. För demonstration har jag anvÀnt Red Hat Enterprise Linux 7.4. VÄrt mÄl Àr att skapa en A-post och en PTR-post för respektive direkt och omvÀnt sök.
Först installerar du de nödvÀndiga rpm-paketen för DNS-servern.
OBS: För RHEL mĂ„ste du ha , eller sĂ„ kan du , vilket gör att paketchefen âyumâ kan installera de nödvĂ€ndiga rpm-paketen och beroenden.
# yum install bind bind-chroot caching-nameserverMina instÀllningar:
# hostname
golinuxhub-client.example
ĐĐŸĐč IP-Đ°ĐŽŃĐ”Ń 192.168.1.7
# ip address | egrep 'inet.*enp0s3'
inet 192.168.1.7/24 brd 192.168.1.255 scope global dynamic enp0s3Eftersom vi kommer att anvÀnda chroot, mÄste tjÀnsten stÀngas av.
# systemctl stop named
# systemctl disable namedKopiera sedan de nödvÀndiga filerna till chroot-katalogen.
OBS. AnvÀnd argumentet -p i kommandot cp för att bevara ÀganderÀtt och rÀttigheter.
[root@golinuxhub-client ~]# cp -rpvf /usr/share/doc/bind-9.9.4/sample/etc/* /var/named/chroot/etc/
â/usr/share/doc/bind-9.9.4/sample/etc/named.confâ -> â/var/named/chroot/etc/named.confâ
â/usr/share/doc/bind-9.9.4/sample/etc/named.rfc1912.zonesâ -> â/var/named/chroot/etc/named.rfc1912.zonesâKopiera sedan zonrelaterade filer till den nya platsen.
[root@golinuxhub-client ~]# cp -rpvf /usr/share/doc/bind-9.9.4/sample/var/named/* /var/named/chroot/var/named/
â/usr/share/doc/bind-9.9.4/sample/var/named/dataâ -> â/var/named/chroot/var/named/dataâ
â/usr/share/doc/bind-9.9.4/sample/var/named/my.external.zone.dbâ -> â/var/named/chroot/var/named/my.external.zone.dbâ
â/usr/share/doc/bind-9.9.4/sample/var/named/my.internal.zone.dbâ -> â/var/named/chroot/var/named/my.internal.zone.dbâ
â/usr/share/doc/bind-9.9.4/sample/var/named/named.caâ -> â/var/named/chroot/var/named/named.caâ
â/usr/share/doc/bind-9.9.4/sample/var/named/named.emptyâ -> â/var/named/chroot/var/named/named.emptyâ
â/usr/share/doc/bind-9.9.4/sample/var/named/named.localhostâ -> â/var/named/chroot/var/named/named.localhostâ
â/usr/share/doc/bind-9.9.4/sample/var/named/named.loopbackâ -> â/var/named/chroot/var/named/named.loopbackâ
â/usr/share/doc/bind-9.9.4/sample/var/named/slavesâ -> â/var/named/chroot/var/named/slavesâ
â/usr/share/doc/bind-9.9.4/sample/var/named/slaves/my.ddns.internal.zone.dbâ -> â/var/named/chroot/var/named/slaves/my.ddns.internal.zone.dbâ
â/usr/share/doc/bind-9.9.4/sample/var/named/slaves/my.slave.internal.zone.dbâ -> â/var/named/chroot/var/named/slaves/my.slave.internal.zone.dbâ
Nu ska vi titta pÄ huvudkonfigurationsfilen.
# cd /var/named/chroot/etc/Rensa innehÄllet i named.conf och klistra in följande.
[root@golinuxhub-client etc]# vim named.conf
options {
listen-on port 53 { 127.0.0.1; any; };
# listen-on-v6 port 53 { ::1; };
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; any; };
allow-query-cache { localhost; any; };
};
logging {
channel default_debug {
file "data/named.run";
severity dynamic;
};
};
view my_resolver {
match-clients { localhost; any; };
recursion yes;
include "/etc/named.rfc1912.zones";
};Information som rör zonen ska lÀggas till i /var/named/chroot/etc/named.rfc1912.zones. LÀgg till posterna som anges nedan. Filen example.zone Àr en fil för direkt visning, och example.rzone Àr filen för omvÀnd zon.
VIKTIG OBS! OmvÀnd visningszon innehÄller 1.168.192 eftersom min IP-adress Àr 192.168.1.7
zone "example" IN {
type master;
file "example.zone";
allow-update { none; };
};
zone "1.168.192.in-addr.arpa" IN {
type master;
file "example.rzone";
allow-update { none; };
};Filer relaterade till zoner finns hÀr:
# cd /var/named/chroot/var/named/LÄt oss nu skapa filer för de direkta och omvÀnda zonerna. Filnamnen kommer att vara desamma som ovan i filen named.rfc1912.zones. Vi har redan nÄgra standardmallar som vi kan anvÀnda.
# cp -p named.localhost example.zone
# cp -p named.loopback example.rzoneSom du ser, har nuvarande behörigheter för alla filer och kataloger tillhör root.
[root@golinuxhub-client named]# ll
total 32
drwxr-xr-x. 2 root root 6 May 22 2017 data
-rw-r--r--. 1 root root 168 May 22 2017 example.rzone
-rw-r--r--. 1 root root 152 May 22 2017 example.zone
-rw-r--r--. 1 root root 56 May 22 2017 my.external.zone.db
-rw-r--r--. 1 root root 56 May 22 2017 my.internal.zone.db
-rw-r--r--. 1 root root 2281 May 22 2017 named.ca
-rw-r--r--. 1 root root 152 May 22 2017 named.empty
-rw-r--r--. 1 root root 152 May 22 2017 named.localhost
-rw-r--r--. 1 root root 168 May 22 2017 named.loopback
drwxr-xr-x. 2 root root 71 Feb 12 21:02 slavesĂndra rĂ€ttigheterna pĂ„ alla filer genom att ange anvĂ€ndaren som Ă€gare root och gruppen named.
# chown root:named *Men för data mÄste Àgaren vara named:named.
# chown -R named:named data
# ls -l
total 32
drwxr-xr-x. 2 named named 6 May 22 2017 data
-rw-r--r--. 1 root named 168 May 22 2017 example.rzone
-rw-r--r--. 1 root named 152 May 22 2017 example.zone
-rw-r--r--. 1 root named 56 May 22 2017 my.external.zone.db
-rw-r--r--. 1 root named 56 May 22 2017 my.internal.zone.db
-rw-r--r--. 1 root named 2281 May 22 2017 named.ca
-rw-r--r--. 1 root named 152 May 22 2017 named.empty
-rw-r--r--. 1 root named 152 May 22 2017 named.localhost
-rw-r--r--. 1 root named 168 May 22 2017 named.loopback
drwxr-xr-x. 2 root named 71 Feb 12 21:02 slavesLÀgg till följande innehÄll i filen för den direkta zonen. HÀr skapar vi en A-post för localhost (golinuxhub-client) och en annan för servern (golinuxhub-server).
# vim example.zone
$TTL 1D
@ IN SOA example. root (
1 ; serial
3H ; refresh
15M ; retry
1W ; expire
1D ) ; minimum
IN NS example.
IN A 192.168.1.7
golinuxhub-server IN A 192.168.1.5
golinuxhub-client IN A 192.169.1.7LÀgg sedan till innehÄllet i filen för den omvÀnda zonen. HÀr skapar vi en PTR-post för golinuxhub-client och för servern golinuxhub-server.
# vim example.rzone
$TTL 1D
@ IN SOA example. root.example. (
1997022700 ; serial
28800 ; refresh
14400 ; retry
3600000 ; expire
86400 ) ; minimum
IN NS example.
5 IN PTR golinuxhub-server.example.
7 IN PTR golinuxhub-client.example.Innan vi startar tjÀnsten named-chroot, kontrollerar vi zonfilens konfiguration.
[root@golinuxhub-client named]# named-checkzone golinuxhub-client.example example.zone
zone golinuxhub-client.example/IN: loaded serial 1
OK
[root@golinuxhub-client named]# named-checkzone golinuxhub-client.example example.rzone
zone golinuxhub-client.example/IN: loaded serial 1997022700
OKAllt ser bra ut. Kontrollera nu konfigurationsfilen med följande kommando.
[root@golinuxhub-client named]# named-checkconf -t /var/named/chroot/ /etc/named.confSÄ, allt Àr klart.
[root@golinuxhub-client named]# echo $?
0VIKTIG NOTERING: jag har SELinux i permissiv lÀge
# getenforce
PermissiveAllt ser bra ut, sÄ det Àr dags att starta vÄr tjÀnst named-chroot .
[root@golinuxhub-client named]# systemctl restart named-chroot[root@golinuxhub-client named]# systemctl status named-chroot
â named-chroot.service - Berkeley Internet Name Domain (DNS)
Loaded: loaded (\/usr\/lib\/systemd\/system\/named-chroot.service; disabled; vendor preset: disabled)
Active: active (running) since Mon 2018-02-12 21:53:23 IST; 19s ago
Process: 5236 ExecStop=\/bin\/sh -c \/usr\/sbin\/rndc stop > \/dev\/null 2>&1 || \/bin\/kill -TERM $MAINPID (code=exited, status=0\/SUCCESS)
Process: 5327 ExecStart=\/usr\/sbin\/named -u named -c ${NAMEDCONF} -t \/var\/named\/chroot $OPTIONS (code=exited, status=0\/SUCCESS)
Process: 5325 ExecStartPre=\/bin\/bash -c if [ ! "$DISABLE_ZONE_CHECKING" == "yes" ]; then \/usr\/sbin\/named-checkconf -t \/var\/named\/chroot -z "$NAMEDCONF"; else echo "Kontroll av zonfiler Àr inaktiverad"; fi (code=exited, status=0\/SUCCESS)
Main PID: 5330 (named)
CGroup: \/system.slice\/named-chroot.service
ââ5330 \/usr\/sbin\/named -u named -c \/etc\/named.conf -t \/var\/named\/chroot
Feb 12 21:53:23 golinuxhub-client.example named[5330]: managed-keys-zone\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone 0.in-addr.arpa\/IN\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone 1.0.0.127.in-addr.arpa\/IN\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone 1.168.192.in-addr.arpa\/IN\/my_resolver: loaded serial 1997022700
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone example\/IN\/my_resolver: loaded serial 1
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone localhost\/IN\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa\/IN\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: zone localhost.localdomain\/IN\/my_resolver: loaded serial 0
Feb 12 21:53:23 golinuxhub-client.example named[5330]: all zones loaded
Feb 12 21:53:23 golinuxhub-client.example named[5330]: running
```bash
Kontrollera att resolv.conf innehÄller din IP-adress sÄ att den kan fungera som en DNS-server.
```bash
# cat \/etc\/resolv.conf
search example
nameserver 192.168.1.7
```bash
LÄt oss kontrollera vÄr DNS-server för den omvÀnda zonen med hjÀlp av dig.
```bash
[root@golinuxhub-client named]# dig -x 192.168.1.5
; <<>> DiG 9.9.4-RedHat-9.9.4-50.el7 <<>> -x 192.168.1.5
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40331
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;5.1.168.192.in-addr.arpa. IN PTR
;; ANSWER SECTION:
5.1.168.192.in-addr.arpa. 86400 IN PTR golinuxhub-server.example.
;; AUTHORITY SECTION:
1.168.192.in-addr.arpa. 86400 IN NS example.
;; ADDITIONAL SECTION:
example. 86400 IN A 192.168.1.7
;; Query time: 1 msec
;; SERVER: 192.168.1.7#53(192.168.1.7)
;; WHEN: Mon Feb 12 22:13:17 IST 2018
;; MSG SIZE rcvd: 122Som du kan se fick vi ett positivt svar (ANSWER) pÄ vÄr förfrÄgan (QUERY).
[root@golinuxhub-client named]# dig -x 192.168.1.7
; <> DiG 9.9.4-RedHat-9.9.4-50.el7 <> -x 192.168.1.7
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55804
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;7.1.168.192.in-addr.arpa. IN PTR
;; ANSWER SECTION:
7.1.168.192.in-addr.arpa. 86400 IN PTR golinuxhub-client.example.
;; AUTHORITY SECTION:
1.168.192.in-addr.arpa. 86400 IN NS example.
;; ADDITIONAL SECTION:
example. 86400 IN A 192.168.1.7
;; Query time: 1 msec
;; SERVER: 192.168.1.7#53(192.168.1.7)
;; WHEN: Mon Feb 12 22:12:54 IST 2018
;; MSG SIZE rcvd: 122PÄ samma sÀtt kan vi kontrollera den direkta zonen.
[root@golinuxhub-client named]# nslookup golinuxhub-client.example
Server: 192.168.1.7
Address: 192.168.1.7#53
Name: golinuxhub-client.example
Address: 192.169.1.7
[root@golinuxhub-client named]# nslookup golinuxhub-server.example
Server: 192.168.1.7
Address: 192.168.1.7#53
Name: golinuxhub-server.example
Address: 192.168.1.5Denna artikel Àr nÄgot förÄldrad, eftersom det numera i RHEL 7 inte behövs att kopiera bind-konfigurationsfiler till chroot. .
KĂ€lla: habr.com
