KEAMANAN INFORMASI DAN ADMINISTRASI JARINGAN OPENCOURSEWARE UNIVERSITAS PEMBANGUNAN JAYA dns server

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PRAKTIKUM ADMINISTRASI

JARINGAN KOMPUTER

DNS SERVER

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PRAKTIKUM ADMINISTRASI

JARINGAN KOMPUTER

DNS SERVER

(Domain Name System)

I. Apa itu DNS?

Domain Name System (DNS) adalah

distribute database system yang digunakan untuk pencarian nama komputer (name resolution) di jaringan yang mengunakan TCP/IP(Transmission Control Protocol/Internet Protocol). DNS biasa digunakan pada aplikasi yangterhubung ke Internet seperti web browser atau e-mail, dimana DNS membantu memetakan host name sebuah komputer ke IP address.

DNS dapat disamakan fungsinya dengan buku telepon.

Dimana setiap komputer dijaringan Internet memiliki host name (nama komputer) dan Internet Protocol (IP) address. Secara umum, setiap client yang akan mengkoneksikan komputer yang satu ke komputer yang lain, akan menggunakan host name.

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Packet Tracer Lab

Working with the Application Layer: DHCP, DNS, and HTTP

This is an example of what your final topology should look like.

Instructions:

1. Start Packet Tracer using Realtime mode.

 Options -> Preferences

 Enable “Show Link Lights”

o Disable “Hide Device Label”

2. Configuring the DHCP Server

Add a server.

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 Change the Display Name to “DHCP Server”  Set the Gateway to 172.16.0.1

FastEthernet:

 Set the IP address to 172.16.0.10  Set the Subnet Mask to 255.255.0.0 HTTP:

 Set HTTP Service and HTTPS Service to Off DHCP:

 Set the Default Gateway to 172.16.0.1  Set the DNS Server to 172.16.0.11  Set the Start IP Address to 172.16.0.100 DNS:

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2. Configuring the DNS Server

Add a server.

Global Settings:

 Change the Display Name to “DNS Server”  Set the Gateway to 172.16.0.1

FastEthernet:

 Set the IP address to 172.16.0.11  Set the Subnet Mask to 255.255.0.0 HTTP:

 Set HTTP Service and HTTPS Service to Off DHCP:

 Set the Service to Off DNS:

 Entering the www.tsrb.edu Domain Name

o Enter for the Domain Name www.tsrb.edu

o Enter for IP Address 172.16.0.20

o Click Add

 Entering the www.internal.com Domain Name

o Enter for the Domain Name www.internal.com

o Enter for IP Address 172.16.0.30

o Click Add

3. Configuring the www.tsrb.edu Web Server

Add a server.

Global Settings:

 Change the Display Name to “Web Server: www.tsrb.edu”  Set the Gateway to 172.16.0.1

FastEthernet:

 Set the IP address to 172.16.0.20  Set the Subnet Mask to 255.255.0.0 DHCP:

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HTTP

 Change the sentence, “<hr>Welcome to Packet Tracer 5.0, the best thing since... Packet Tracer 4.0.” to “<hr> Welcome to Tsrb's public web page!” You may add other information as well.

4. Configuring the www.internal.com Web Server

Add a server.

Global Settings:

 Change the Display Name to “Web Server: www.internal.com”  Set the Gateway to 172.16.0.1

FastEthernet:

 Set the IP address to 172.16.0.30  Set the Subnet Mask to 255.255.0.0 DHCP:

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HTTP

 Change the sentence, “<hr>Welcome to Packet Tracer 5.0, the best thing since... Packet Tracer 4.0.” to “<hr> This is the corporate internal network!” You may add other information as well.

5. Configure Two Client Computers using DHCP

Add two client computers.

Global Settings:

 Change the Display Names to “Dynamic 1” and to “Dynamic 2” respectively  Set the Gateway/DNS to DHCP

FastEthernet:

 Set the IP Configuration to DHCP

6. Configure One Client Computers using Static IP Addressing

Add two client computers.

Global Settings:

 Change the Display Name to “Static”  Set the Gateway/DNS to Static

 Set Gateway to 172.16.0.1  Set the DNS Server to 172.16.0.11 FastEthernet:

 Be sure the configuration is set to Static  Set the IP address to 172.16.0.90  Set the Subnet Mask to 255.255.0.0

7. Adding switches

 Add two switches.

 Connect the servers to one switch using a straight-through cable.

 Connect the client computers to the other switch using a straight-through cable.  Interconnect the two switches using a crossover cable.

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 Ping (ICMP)

o From a client computer use the Desktop Command prompt to ping the other client computers and the servers.

o Example: From the Dynamic 1 client, C> ping 172.16.0.20

o The first one or two pings may fail, but you should receive a reply on the later pings. This is due to the ping timing out while the ARP process takes place (later).

 Web Browser (HTTP)

o On the client computers use the Desktop Web Browser, enter the URLs of the Web Servers www.tsrb.edu and www.internal.com.

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9. Using Simulation Mode

Click on Simulation.

Note: To reset a simulation, click on “Reset Simulation”

Click on Edit Filters

 Choose Show All/None so that all the boxes (protocols) are unchecked.  Select (check) the following protocols: DHCP, ICMP, HTTP, DNS.

Web Browser (HTTP)

 On the client computers use the Desktop Web Browser, enter the URLs of the Web Servers www.tsrb.edu or www.internal.com.

 Click on Auto Capture/Play (automatically forwards the packets) or Capture Forward (must keep clicking to advance the packets)

DHCP

 Reset the simulation by clicking on “Reset Simulation”

 To view DHCP, on one of the “Dynamic “client computers using DHCP go to the Desktop Command prompt.

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II. DNS Server Linux

1.

Installasi bind9

# apt-get install bind9

2.

Catatlah di direktori mana saja program DHCP server diinstall

# dpkg –L bind9

3.

Konfigurasi file /etc/resolv.conf

File /etc/resolv.conf perlu dikonfigurasi

untuk menyeting komputer yang kita gunakan

adalah sebagai DNS Server maka option nameserver kita isi dengan nomor IP

address dari IP dari komputer itu sendiri.

# vim /etc/resolv.conf

domain nano.co.id

search nano.co.id

nameserver 10.252.108.45

4.

Copy template database ke /var/cache/bind

# cp /etc/bind/db.local /var/cache/bind/nano.co.id.db

# cp /etc/bind/db.255 /var/cache/bind/nano.co.id.rev

5.

Edit file database file

# vim /var/cache/bind/nano.co.id.db

;

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;

Edit file database reverse file

# vim /var/cache/bind/nano.co.id.rev

;

; BIND reverse data file for broadcast zone

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604800 ) ; Negative Cache TTL

;

@ IN NS localhost.

45 IN PTR www.nano.co.id.

54 IN PTR chan.nano.co.id

7. Edit file configurasi named.conf.local

# vim /etc/bind/named.conf.local

//

// Do any local configuration here

//

// Consider adding the 1918 zones here, if they are not used in your

// organization

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forwarders {

auth-nxdomain yes; # conform to RFC1035

listen-on-v6 { any; };

};

9. Restart bind9

# /etc/init.d/bind9 restart

10. Cek dengan menggunakan nslookup

# nslookup www.nano.co.id

III Dynamic DNS Server

1. Installasi DHCP3 seperti pada praktikum DHCP

2. Memasukkan key penanda pada bind

# vim /etc/bind/named.conf.local

Tambahkan baris dibawah ini pada bagian paling atas dari script:

include "/etc/bind/rndc.key";

controls {

inet 127.0.0.1 port 953

allow {

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} keys { "rndc-key"; };

};

Catatan: key (seperti rndc.key) dapat di buat sendiri dengan cara

# dnssec-keygen -a hmac-md5 -b 128 -n user <nama-key>

Tambahkan scrip dibawah ini:

notify yes;

allow-update {

127.0.0.1;

key "rndc-key";

};

Sehingga file /etc/bind/named.conf.local menjadi :

controls {

inet 127.0.0.1 port 953

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};

# /etc/init.d/bind9 restart

4.Edit file configurasi dhcp3

# vim /etc/dhcp3/dhcpd.conf

Tambahkan baris dibawah ini pada bagian paling atas dari script:

ddns-updates

on;

ddns-update-style

interim;

ddns-domainname "nano.co.id";

ddns-rev-domainname "in-addr.arpa";

zone nano.co.id. {

primary 127.0.0.1;

key rndc-key;

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zone 108.252.10.in-addr.arpa. {

primary 127.0.0.1;

key rndc-key;

}

5. Restart dhcp3

# /etc/init.d/dhcp3-server restart

6. Konfigurasi di client

# vim /etc/dhcp3/dhclient.conf

send host-name "eclipse";