Boot Process in Linux

To View the default runlevel while booting the Linux Operating System
[root@tsmservertest ~]# vi /etc/inittab

id:5:initdefault:  (End of the line in Fedora OS)

Note: It means that OS by default always boot to GUI mode.


To View the current runlevel

[root@tsmservertest ~]# runlevel
N 5


To Switch to another runlevel and check the runlevl
[root@tsmservertest ~]# init 3
[root@tsmservertest ~]# runlevel
5 3

[root@tsmservertest ~]# init 2
[root@tsmservertest ~]# runlevel
3 2


[root@tsmservertest ~]# init 1
[root@tsmservertest ~]# runlevel
1 S


[root@tsmservertest ~]# init 6


To View the grup configuration file


[root@localhost ~]# cat /boot/grub/grub.conf

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Backup and Recovery

Create a folder
for EX:-- /myfolder

[root@tsmservertest ~]# mkdir /myfolder
[root@tsmservertest ~]# cd /myfolder/

Now create Some files and folders inside it.

[root@tsmservertest myfolder]# mkdir dir1
[root@tsmservertest myfolder]# touch 1 songs tom_file
[root@tsmservertest myfolder]# ls
1  dir1  songs  tom_file


Use the tar command to tape archive the folder

[root@tsmservertest ~]# tar -cvf /opt/myfolder.tar /myfolder
tar: Removing leading `/' from member names
/myfolder/
/myfolder/tom_file
/myfolder/dir1/
/myfolder/songs
/myfolder/1

[root@tsmservertest ~]# cd /opt/
[root@tsmservertest opt]# ls -l
total 12
-rw-r--r-- 1 root root 10240 Oct 22 13:01 myfolder.tar


To Create a tar file with zip

[root@tsmservertest opt]# cd
[root@tsmservertest ~]# tar -cvzf /opt/myfolder.tar.gz /myfolder/
#########OUTPUT#############
tar: Removing leading `/' from member names
/myfolder/
/myfolder/tom_file
/myfolder/dir1/
/myfolder/songs
/myfolder/1
[root@tsmservertest ~]# cd /opt/
[root@tsmservertest opt]# ls -l
total 16
-rw-r--r-- 1 root root 10240 Oct 22 13:01 myfolder.tar
-rw-r--r-- 1 root root   194 Oct 22 13:10 myfolder.tar.gz


To View the contents of the tar file without extracting

[root@tsmservertest opt]# tar -tvzf /opt/myfolder.tar.gz
drwxr-xr-x root/root         0 2011-10-22 12:58 myfolder/
-rw-r--r-- root/root         0 2011-10-22 12:58 myfolder/tom_file
drwxr-xr-x root/root         0 2011-10-22 12:58 myfolder/dir1/
-rw-r--r-- root/root         0 2011-10-22 12:58 myfolder/songs
-rw-r--r-- root/root         0 2011-10-22 12:58 myfolder/1

To remove the folder

[root@tsmservertest ~]# rm -r /myfolder/
rm: descend into directory `/myfolder'? y
rm: remove regular empty file `/myfolder/tom_file'? y
rm: remove directory `/myfolder/dir1'? y
rm: remove regular empty file `/myfolder/songs'? y
rm: remove regular empty file `/myfolder/1'? y
rm: remove directory `/myfolder'? y
[root@tsmservertest ~]# cd /


To extract the tar file or recovery the data

[root@tsmservertest /]# tar -xvzf /opt/myfolder.tar.gz
myfolder/
myfolder/tom_file
myfolder/dir1/
myfolder/songs
myfolder/1


After extracting see the contents inside the folder

[root@tsmservertest /]# ls /myfolder/
1  dir1  songs  tom_file

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