====== Yum ======
YUM is the package management tool that help to install or update the package through the network or local, the same time it provides easy method to install a package with it’s dependent packages. Configuration files are under /etc directory, /etc/yum.conf is the mail global file that contains the global options such as cache directory,log directory etc… To add new or update the existing repository, you must got to the /etc/repos.d directory and create or open a file that ends on .repo respectively.

===== CDROM/DVD =====

First you must determine the name of the CD-ROM or DVD drive and there are 3 methods:

**[a] dmesg Command**

dmesg command is used to examine the Linux kernel ring buffer i.e. display bootup messages on screen. To find out if cdrom was detected or not, run:

<code>
bash# dmesg | egrep -i --color 'cdrom|dvd|cd/rw|writer'

ata2.00: ATAPI: VMware Virtual IDE CDROM Drive, 00000001, max UDMA/33
sr0: scsi3-mmc drive: 1x/1x writer dvd-ram cd/rw xa/form2 cdda tray
</code>

**[b] /proc/sys/dev/cdrom/info file name.**

<code>
bash# cat /proc/sys/dev/cdrom/info

CD-ROM information, Id: cdrom.c 3.20 2003/12/17

drive name:             sr0
drive speed:            1
drive # of slots:       1
Can close tray:         1
Can open tray:          1
Can lock tray:          1
Can change speed:       1
Can select disk:        0
Can read multisession:  1
Can read MCN:           1
Reports media changed:  1
Can play audio:         1
Can write CD-R:         1
Can write CD-RW:        1
Can read DVD:           1
Can write DVD-R:        1
Can write DVD-RAM:      1
Can read MRW:           1
Can write MRW:          1
Can write RAM:          1

bash#
</code>

**[c] lsblk command**

<code>
bash# lsblk

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    1   558G  0 disk
├─sda1   8:1    1   307M  0 part /boot
├─sda2   8:2    1   250G  0 part /datasql
├─sda3   8:3    1     6G  0 part [SWAP]
├─sda4   8:4    1     1K  0 part
└─sda5   8:5    1 301.7G  0 part /
sr0     11:0    1  1024M  0 rom  

</code>

===== Mount CDROM/DVD =====

Insert the Red Hat Enterprise Linux Server DVD into your DVD-ROM drive and mount the CD/DVD ROM on the any directory of your wish, for testing mount it on /mnt/cdrom.

<code>
bash# mkdir /mnt/cdrom

bash# mount /dev/sr0 /mnt/cdrom
</code>

===== Config Repository =====

Create a new repository file.

<code>
bash# vi /etc/yum.repos.d/rhel-dvd.repo

[dvd]
name=DVD Repo
baseurl=file:///mnt/cdrom
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release
</code>

===== Install from CDROM/DVD =====

Now you should be able to install from CDROM or DVD

<code>
bash# yum install <packages>
</code>