Kursa studentiem sagatavots raksta tulkojums
Šajā rakstā es jums pastāstīšu, kā iestatīt DNS serveri operētājsistēmā RHEL 7 vai CentOS 7. Demonstrācijai izmantoju Red Hat Enterprise Linux 7.4. Mūsu mērķis ir izveidot vienu A ierakstu un vienu PTR ierakstu attiecīgi uz priekšu un atpakaļ uzmeklēšanas zonām.
Vispirms instalējiet DNS serverim nepieciešamās rpm pakotnes.
PIEZĪME: RHEL jums ir jābūt
# yum install bind bind-chroot caching-nameserver
Mani iestatījumi:
# hostname
golinuxhub-client.example
Мой IP-адрес 192.168.1.7
# ip address | egrep 'inet.*enp0s3'
inet 192.168.1.7/24 brd 192.168.1.255 scope global dynamic enp0s3
Tā kā mēs izmantosim chroot, mums ir jāatspējo pakalpojums.
# systemctl stop named
# systemctl disable named
Pēc tam kopējiet nepieciešamos failus chroot direktorijā.
PIEZĪME. Izmantojiet argumentu -p komandā cp lai saglabātu tiesības un īpašniekus.
[root@golinuxhub-client ~]# cp -rpvf /usr/share/doc/bind-9.9.4/sample/etc/* /var/named/chroot/etc/
‘/usr/share/doc/bind-9.9.4/sample/etc/named.conf’ -> ‘/var/named/chroot/etc/named.conf’
‘/usr/share/doc/bind-9.9.4/sample/etc/named.rfc1912.zones’ -> ‘/var/named/chroot/etc/named.rfc1912.zones’
Pēc tam kopējiet ar zonu saistītos failus uz jaunu vietu.
[root@golinuxhub-client ~]# cp -rpvf /usr/share/doc/bind-9.9.4/sample/var/named/* /var/named/chroot/var/named/
‘/usr/share/doc/bind-9.9.4/sample/var/named/data’ -> ‘/var/named/chroot/var/named/data’
‘/usr/share/doc/bind-9.9.4/sample/var/named/my.external.zone.db’ -> ‘/var/named/chroot/var/named/my.external.zone.db’
‘/usr/share/doc/bind-9.9.4/sample/var/named/my.internal.zone.db’ -> ‘/var/named/chroot/var/named/my.internal.zone.db’
‘/usr/share/doc/bind-9.9.4/sample/var/named/named.ca’ -> ‘/var/named/chroot/var/named/named.ca’
‘/usr/share/doc/bind-9.9.4/sample/var/named/named.empty’ -> ‘/var/named/chroot/var/named/named.empty’
‘/usr/share/doc/bind-9.9.4/sample/var/named/named.localhost’ -> ‘/var/named/chroot/var/named/named.localhost’
‘/usr/share/doc/bind-9.9.4/sample/var/named/named.loopback’ -> ‘/var/named/chroot/var/named/named.loopback’
‘/usr/share/doc/bind-9.9.4/sample/var/named/slaves’ -> ‘/var/named/chroot/var/named/slaves’
‘/usr/share/doc/bind-9.9.4/sample/var/named/slaves/my.ddns.internal.zone.db’ -> ‘/var/named/chroot/var/named/slaves/my.ddns.internal.zone.db’
‘/usr/share/doc/bind-9.9.4/sample/var/named/slaves/my.slave.internal.zone.db’ -> ‘/var/named/chroot/var/named/slaves/my.slave.internal.zone.db’
```bash
Теперь давайте посмотрим на основной файл конфигурации.
```bash
# cd /var/named/chroot/etc/
Notīriet faila named.conf saturu un ielīmējiet tālāk norādīto.
[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";
};
Jāpievieno informācija par specifisku zonu /var/named/chroot/etc/named.rfc1912.zones. Pievienojiet ierakstus zemāk. Fails example.zone ir uzmeklēšanas zonas fails un piemērs.rzone — apgrieztās zonas fails.
SVARĪGA PIEZĪME. Apgrieztās meklēšanas zonā ir 1.168.192, jo mana IP adrese ir 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; };
};
Ar zonām saistītie faili atrodas šeit:
# cd /var/named/chroot/var/named/
Tālāk mēs izveidosim failus uz priekšu un atpakaļgaitu zonām. Failu nosaukumi būs tādi paši kā iepriekš failā named.rfc1912.zones. Mums jau ir vairākas noklusējuma veidnes, kuras varam izmantot.
# cp -p named.localhost example.zone
# cp -p named.loopback example.rzone
Kā redzat, pašreizējās atļaujas visiem failiem un direktorijiem pieder sakne.
[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 slaves
Mainiet visu failu atļaujas, lai norādītu lietotāju kā īpašnieku sakne un grupa nosaukts.
# chown root:named *
Bet datu īpašniekam ir jābūt nosaukts:nosaukts.
# 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 slaves
Pievienojiet tālāk norādīto saturu savam pārsūtīšanas zonas failam. Šeit mēs izveidojam A ierakstu vietējam resursdatoram (golinuxhub-client) un otru serverim (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 192.169.1.7
Pēc tam pievienojiet saturu reversās zonas failam. Šeit mēs izveidojam PTR ierakstu golinuxhub-klientam un golinuxhub-serverim.
# 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.
Pirms pakalpojuma palaišanas nosaukts-chroot, pārbaudīsim zonas faila konfigurāciju.
[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
OK
Viss izskatās labi. Tagad pārbaudiet konfigurācijas failu, izmantojot šo komandu.
[root@golinuxhub-client named]# named-checkconf -t /var/named/chroot/ /etc/named.conf
Tātad viss tika veiksmīgi pabeigts.
[root@golinuxhub-client named]# echo $?
0
SVARĪGA PIEZĪME. Man SELinux ir atļautā režīmā
# getenforce
Permissive
Viss izskatās labi, tāpēc ir pienācis laiks uzsākt mūsu pakalpojumu nosaukts-chroot .
[root@golinuxhub-client named]# systemctl restart named-chroot
[root@golinuxhub-client named]# systemctl status named-chroot
● 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 "Checking of zone files is disabled"; fi (code=exited, status=0/SUCCESS)
Main PID: 5330 (named)
CGroup: /system.slice/named-chroot.service
└─5330 /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
Убедитесь, что resolv.conf содержит ваш IP-адрес, чтобы он мог работать в качестве DNS-сервера.
```bash
# cat /etc/resolv.conf
search example
nameserver 192.168.1.7
```bash
Давайте проверим наш DNS-сервер для обратной зоны, используя 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: 122
Kā redzat, mēs saņēmām pozitīvu atbildi (ANSWER) uz mūsu pieprasījumu (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: 122
Tādā pašā veidā varam pārbaudīt tiešo zonu.
[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: 192.168.1.5
Šis raksts ir nedaudz novecojis, jo RHEL 7 jums vairs nav jākopē saistīšanas konfigurācijas faili chroot.
Avots: www.habr.com