Mwongozo wa hatua kwa hatua wa kusanidi seva ya BIND DNS katika mazingira ya chroot ya Red Hat (RHEL/CentOS) 7

Tafsiri ya makala iliyotayarishwa kwa wanafunzi wa kozi "Usalama wa Linux". Je, ungependa kuendeleza katika mwelekeo huu? Tazama rekodi ya utangazaji wa darasa la bwana la Ivan Piskunov "Usalama katika Linux ikilinganishwa na Windows na MacOS"

Mwongozo wa hatua kwa hatua wa kusanidi seva ya BIND DNS katika mazingira ya chroot ya Red Hat (RHEL/CentOS) 7

Katika makala hii, nitakutembeza kupitia hatua za kusanidi seva ya DNS kwenye RHEL 7 au CentOS 7. Nilitumia Red Hat Enterprise Linux 7.4 kwa maandamano. Lengo letu ni kuunda rekodi moja ya A na rekodi moja ya PTR kwa ajili ya maeneo ya kuangalia mbele na nyuma, mtawalia.

Kwanza, sakinisha vifurushi muhimu vya rpm kwa seva ya DNS.

KUMBUKA: Kwa RHEL lazima uwe nayo Usajili unaotumika wa RHN, au unaweza weka hazina ya ndani ya nje ya mtandao, ambayo msimamizi wa kifurushi "yum" anaweza kusakinisha vifurushi muhimu vya rpm na utegemezi.

# yum install bind bind-chroot caching-nameserver

Mipangilio yangu:

# 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

Kwa kuwa tutatumia chroot, tunahitaji kuzima huduma.

# systemctl stop named
# systemctl disable named

Kisha nakala faili zinazohitajika kwenye saraka ya chroot.
KUMBUKA. Tumia hoja -p katika timu cp kuhifadhi haki na wamiliki.

[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’

Kisha nakili faili zinazohusiana na eneo kwenye eneo jipya.

[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/

Futa yaliyomo kwenye name.conf na ubandike yafuatayo.

[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";
};

Taarifa mahususi za eneo lazima ziongezwe kwa /var/named/chroot/etc/named.rfc1912.zones. Ongeza maingizo hapa chini. Faili ya example.zone ni faili ya eneo la kuangalia mbele, na mfano.rzone - faili ya eneo la nyuma.

KUMBUKA MUHIMU: Eneo la kuangalia kinyume lina 1.168.192 kwa sababu anwani yangu ya IP ni 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; };
};

Faili zinazohusishwa na kanda ziko hapa:

# cd /var/named/chroot/var/named/

Ifuatayo, tutaunda faili za kanda za mbele na za nyuma. Majina ya faili yatakuwa sawa na hapo juu kwenye faili iliyopewa jina.rfc1912.zones. Tayari tuna violezo kadhaa chaguo-msingi ambavyo tunaweza kutumia.

# cp -p named.localhost  example.zone
# cp -p named.loopback example.rzone

Kama unavyoona, ruhusa za sasa kwenye faili na saraka zote ni za mizizi.

[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

Badilisha ruhusa za faili zote ili kuonyesha mtumiaji kama mmiliki mizizi na kikundi jina lake.

# chown root:named *

Lakini kwa data mmiliki lazima awe jina: jina.

# 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

Ongeza maudhui yafuatayo kwenye faili yako ya eneo la mbele. Hapa tunaunda rekodi ya A kwa localhost (mteja wa golinuxhub) na nyingine kwa seva (seva ya golinuxhub).

# 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

Ifuatayo, ongeza yaliyomo kwenye faili ya eneo la nyuma. Hapa tunaunda rekodi ya PTR kwa mteja wa golinuxhub na seva ya golinuxhub.

# 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.

Kabla ya kuzindua huduma jina-chroot, hebu tuangalie usanidi wa faili ya eneo.

[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

Kila kitu kinaonekana vizuri. Sasa angalia faili ya usanidi kwa kutumia amri ifuatayo.

[root@golinuxhub-client named]# named-checkconf -t /var/named/chroot/ /etc/named.conf

Kwa hivyo, kila kitu kilikamilishwa kwa mafanikio.

[root@golinuxhub-client named]# echo $?
0

KUMBUKA MUHIMU: Nina SELinux katika hali ya kuruhusu

# getenforce
Permissive

Kila kitu kinaonekana vizuri, kwa hivyo ni wakati wa kuzindua huduma yetu jina-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

Kama unavyoona, tulipokea jibu chanya (JIBU) kwa ombi letu (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

Tunaweza kuangalia ukanda wa moja kwa moja kwa njia sawa.

[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

Makala haya yamepitwa na wakati kwani katika RHEL 7 huhitaji tena kunakili faili za usanidi za kuunganisha kwenye chroot. Mafunzo ya Hatua kwa Hatua: Sanidi Seva ya DNS kwa kutumia bind chroot (CentOS/RHEL 7).

Chanzo: mapenzi.com

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