RedHat Linux Certification mode preparation

Domain Name System[DNS]

Domain Name System[DNS]:

Definition:

It is a service and it translate to human readable domain name to ip and vice versa.
DNS server name contain webserver name & IP.
home ____ ISP ____ DNS _____ webserver
Virtual Hosting:
one IP contains more than one names. Its called website.
Example:
linux.com[website],IP 192.168.0.65
-it will register to DNS.
SERVER CONFIGURATION FILE SYSTEM:

#/var/named/chroot/etc
#vi named.conf
zone "linux.com In {
type master;
file "nita.zone"
}
To create DB file name:[linux.zone]
cd /var/named/chroot/var/named
cp localdomain.zone linux.zone
vi linux.zone
localhost root {
system4

IN ANS [localhost] system4

linux.com IN A 192.168.0.65 [web server name]

}

CLIENT CONFIGURATION:

Then Next Step:
vi /etc/hosts
192.168.0.0/16
vi /etc/resolv.conf
nameserver 192.168.0.4 assign DNS address
dig linux.com
vi /etc//httpd/conf/httpd.conf
go for last line.

Document Root /var/www/html
ServerName system4

Virtual Host:
More then one web server to be formed. It's called virtual host.

Note:
Package Name:
Server side:named
Client side: httpd

Tellnet

Tellnet:

- For remote login from windows to linux and not vice versa.But can also linux to linux

Configuration:
vi /etc/xinetd.d/telnet
disable= no

# service xinetd reload
# chkconfig xinetd on
testparm --> to view the share user's.

Note:
Package Name: xinittelnet
Service Name: xinetd

Remote Login

REMOTE LOGIN:

-- To connect witha network system in same operating system(os-linux) family.
Configuration:
--> vi /etc/xinetd.d/rlogin
--dsiable='no'
service xinetd reload
chkconfig xinetd on

Note:
Package Name:xinetd.d
Service Name:xinetd

Basic and Advanced Linux Command

Basic and Advanced Linux Command:

--> To transfer the file from source to desination machine
Purpose:
Download(Source to desination)
Upload(Desination to source)
#vi /etc/vsftpd/vsftpd.conf
#setsebool -P allow_ftpd_full_access 0

#service vsftpd reload
#chkconfig vsftpd on

Note: Package Name:vsftpd

DHCP[Dynamic Host Configuration Protocol]

DHCP[Dynamic Host Configuration Protocol]:

--> to assign IP address automatically
Step:
#/usr/share/doc-3.0.5/dhcpd.conf copy to vi /etc/dhcpd.conf
Install Package
rpm -ivh dhcp
t0 configuration file
vi /etc/dhcpd.conf
activate the services
service dhcpd restart
Open to Configuration file:
range subnetmask netid
192.168.1.1 to 192.168.1.248 255.255.255.0 192.168.1.240

--> To Manually assign to IP for which system you need to assign as a Server Machine.

Note:
Package Name:dhcpd

TCP/IP [Transmission Control Protocol&Internet Protocol]

TCP/IP [Transmission Control Protocol&Internet Protocol]:

Definition: It is used for Communicating the system in a network. It means set of rules. Actually TCP/IP was designed for unix family but it will be support for all type of operating system. So it is a platform independent. It's called Internet Protocols. Its Control mainly IP address. Two types of ADDRESS:
software address: It's a network IP address , 32-bit address.
Hardware address It's a network MAC address , 48-bit address.


                                                                                                                                                                                                                                                 IP    MAC
Assigned by Administrator    Assigned by Manufactured concern.
It means nic[network interface card]
Temporary address.    Permanent address
Example: Router Identification.

Software IP address: It's a 32-bit address. It's caontain four octal-bit

8       8       8       8
w       x       y       z

--to identify amachine in a network.

W min value 0000 0000
W max value 1111 1111

Types of Classes:               Range

CLASS A
                             0-126       127 as aloop backup.It's means that controlling the network devices.
CLASS B                             128-191
CLASS C                             192-223
CLASS D                             224-239
CLASS E                             240-255

CLASS A
IP Address Contains two parts Net ID Host ID

8       8       8       8
w       x       y       z
|
|
/
W as a Net ID        then another x,y,z as a Host ID.

Types of Octal ID:               Range

W                                                  0-126
X                                                   0-255
Y                                                   0-255
Z                                                   0-255

CLASS B
IP Address Contains two parts Net ID Host ID

8       8       8       8
w       x       y       z
|______|
     |
     |
    /
W ,X as a Net ID   Y,Z as a Host ID.

Types of Octal ID:               Range

W                                                  0-126
X                                                   0-255
Y                                                   0-255
Z                                                   0-255

CLASS C
IP Address Contains two parts Net ID Host ID

8       8       8       8
w       x       y       z
|__________|
        |
        |
       /
W ,X,Y as a Net ID        Z as a Host ID.

Types of Octal ID:               Range

W                                                  0-126
X                                                   0-255
Y                                                   0-255
Z                                                   0-255

CLASS D

IP Address Contains two parts Net ID Host ID

8       8       8       8
w       x       y       z
|_______________|-->         W X,Y,Z as a Net ID.

Types of Octal ID:               Range

W                                                  0-126
X                                                   0-255
Y                                                   0-255
Z                                                   0-255

CLASS E

--Its a Reserved for future Purpose Only.

Note: Netbeu was designed for windows family. IPx/SPx was designed for Novell Network.