Shell Script

#Next line tell with shell to use
#!/bin/bash

#we store in variable path to file
UserListFile=/tmp/user.list

#We create function with name Usage
Usage () {

#printing help
echo “$0 – execute command in all HOME directories

usage: $0 [-a] command [arg ...]

-a: process HOME directories of all users

The given command will be executed with the arguments specified in the

home directory of users.

”

#exit from program
exit 1

#end of function
}

#we check if there less than 1 parameter
if [ $# -lt 1 ]

then

#if less – print help
Usage

#in other case
else

#we check passed parameters, starting from first
case “$1″ in

#if parameter -a then we write to All variable value true
-a) All=true

#removing parameter
shift ;;

#if parameter starting with -, and not -a, we print help
-*) Usage ;;

#exit from case
esac

#exit from fi loop
fi

#we check if user pass -a as parameter
if [ "$All" = true ]

#if -a passed
then

#we get list of all users
cat /etc/passwd | cut -d’:’ -f1 | sed -e ‘s/:/ /g’ > $UserListFile

# in other case
else

#print message
echo “Please enter users, type [ to exit"

#cleaning file with userlist
echo -n > $UserListFile

#starting while loop to read users
while read UserName Rest

do

#if user print [ to exit loop
if [ $UserName = "[" ]; then

#exit from loop
break

#if user print other data
else
#we check if user put any symbol

test -z “$UserName” && continue
#we check if user exist
grep “^$UserName” /etc/passwd > /dev/null || {

#if not exist print message to user
echo “Can’t find user ${UserName}; ignored.”

#we continue loop
continue

}

#if user exist – we store it to userfile
echo $UserName >> $UserListFile

#exit of if loop
fi

#exit from reading user input
done

#exit from if loop
fi

#just print empty line
echo “”

#stop all other parameters as command we need to run
Command=”$@”

#getting list of users
UserList=`cat $UserListFile`

#getting user one by one from list
for user in ${UserList}

do

#one more empty line
echo “”

#getting user home directory
HomeDir=`grep “^$user” /etc/passwd | cut -d”:” -f6`

# we check if we have read and execute permissions to cd and run command
[ -r "$HomeDir" -a -x "$HomeDir" ] || {

# if not just warn user
echo “Read or execute of folder $HomeDir denied”

continue

#exit of check
}

#we telling user about what command we run and inside what directory
echo “Runnig $Command inside $HomeDir”

#entering home
cd $HomeDir

#running command
$Command

done
#cleaning, removing temp files
rm -rf $UserListFile

Sccript Output

./exec_home.sh ls

Please enter users, type exit to exit

sshd

yevhen

exit

Runnig ls inside /var/run/sshd

Runnig ls inside /home/yevhen

Desktop Downloads examples.desktop Pictures Templates

Documents Dropbox Music Public Videos

The post Shell Script To Run Commands In Users Home Directory appeared first on ExpertsLogIn.

Shell Script

#!/bin/bash

#file, where we will store full list of files.
ListOfFiles=/tmp/listoffiles.txt

#we ask user to enter directory where search for duplicated files
echo -n “Please enter directory where to search for duplicated files: ”

#we read user input
while read dir

do

#we check if user input is not empty
test -z “$dir” && {

#if user input empty we ask once more to enter directory
echo -n “Please enter directory: ”

continue

}

#if directory entered, exit from while loop
break

done

#getting list of files inside entered directory
find $dir -type f -print > $ListOfFiles

#writing list of files to variable
FileList=`cat $ListOfFiles`

#we get number of files
count=`wc -l $ListOfFiles| awk ‘{print $1}’`

#counter
i=1

#we get files one by one
for file in $FileList

do

#just make this variable empty for every loop
samefiles=”"

#we need to get all non-proceeded files
let tailvalue=$count-$i

#we get only filename, without path
filename=$(basename $file)

#getting list of un-proceeded files, and we check if there is file with same filename
samefiles=`tail -${tailvalue} $ListOfFiles | grep $filename`

#starting loop for all same files
for samefile in $samefiles

do

#we get md5sum of filename with same name
msf=`md5sum $samefile | awk ‘{print $1}’`

#we get md5sum of original file
ms=`md5sum $file | awk ‘{print $1}’`

#we compare md5sums
if [ "$msf" = "$ms" ]; then

#if md5sums equal, we tell user about duplicated files
echo “File $file duplicated to $samefile”

#end of if loop
fi

#end of while loop
done

#increase counter by 1
let i=$i+1

done

Script Output

./finddup.sh

Please enter directory where to search for duplicated files: /tmp

File /tmp/1/user.list duplicated to /tmp/user.list

The post Shell Script To Delete Duplicate Files appeared first on ExpertsLogIn.

Commands used are du with different keys , then sort and head commands.

Shell script

#/bin/bash

#check if user input argument

if [ $# -eq 0 ]; then

#if no argument print next messge and exit from script
echo “Usage: $0 ”

exit 1

fi
# Save first arguments to variables
CheckedDir=”$1″
#
HeadValue=$2
#set value for variable count value 1
count=1

#just print empty line
echo “”

#Print next message:
echo “Here is the ${HeadValue} biggest directories located in ${CheckedDir}:”

echo “”

#Getting list of directories and space they use.
du -a –max-depth=1 –one-file-system ${CheckedDir}/ |

#next we sort result
sort -rn |

sed “1d” |

# next we get only first X directories
head -”${HeadValue}” |

#next print result to user
while read size dirrr ; do
#counting size in Mb

size=”$(( size / 1024 ))”

#show output for user
echo “N°${count} : ${dirrr} is ${size} Mb”

((count++))

done

echo “”

Script Output

./top5dir.sh /home/yevhen/

Here is the biggest directories located in /home/yevhen/:

N°1 : /home/yevhen//Fly is 14043 Mb

N°2 : /home/yevhen//VirtualBox VMs is 5837 Mb

N°3 : /home/yevhen//Downloads is 2224 Mb

N°4 : /home/yevhen//.icedove is 963 Mb

N°5 : /home/yevhen//Downloads is 645 Mb

N°6 : /home/yevhen//.wine is 602 Mb

N°7 : /home/yevhen//.cache is 324 Mb

N°8 : /home/yevhen//Dropbox is 324 Mb

N°9 : /home/yevhen//.config is 263 Mb

N°10 : /home/yevhen//.local is 153 Mb

The post Shell Script To Find Directories Which Consume Highest Space appeared first on ExpertsLogIn.

#!/bin/bash

#clear console
clear

#just echo welcome messages
echo “This is information provided by $0 . Program starts now.”

echo “Hello, $USER”

echo

#print today’s date
echo “Today’s date is `date`, this is week `date +”%V”`.”

echo

#list of currently loged user via w command.
echo “These users are currently connected:”

w | cut -d ” ” -f 1 – | grep -v USER | sort -u

echo

#info about system with command uname and keys -m and -s
echo “This is `uname -s` running on a `uname -m` processor.”

echo

#info about uptime, using uptime command
echo “This is the uptime information:”

uptime

echo

#info about free memory via free command
echo “Free memory:”

free

echo

#info about disk usage
echo “Disk usage:”

df -kh

echo

Output

Below is the script output.

This is information provided by ./system_info.sh . Program starts now.

Hello, yevhen

Today’s date is Sunday, March 3 2013 22:31:43 +0200, this is week 09.

These users are currently connected:

yevhen

This is Linux running on a i686 processor.

This is the uptime information:

22:31:43 up 1:24, 2 users, load average: 0.45, 0.18, 0.07

Free memory:

total used free shared buffers cached

Mem: 3374792 1589476 1785316 0 96720 725652

-/+ buffers/cache: 767104 2607688

Swap: 4192924 0 4192924

Disk usage:

Filesystem Size Used Avail Use% mounted
/dev/sda1 42G 5,5G 35G 14% /

tmpfs 1,7G 0 1,7G 0% /lib/init/rw

udev 1,7G 168K 1,7G 1% /dev

tmpfs 1,7G 160K 1,7G 1% /dev/shm

/dev/sda6 184G 26G 149G 15% /home

The post Shell Script To Collect Linux System Information appeared first on ExpertsLogIn.

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df command options

Without any switch, df displays all mounted filesystems. The default output shows columns for following information: ‘Filesystem’, ’1K-blocks’, ‘Used’(used blocks), ‘Available’(blocks), ‘use%’(the %age of used blocks againsta total number of blocks in a filesystem) and ‘Mounted on’(the mount point of a filesystem).

$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468104 3098980 68% /
udev 1521232 4 1521228 1% /dev
tmpfs 613188 1164 612024 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 8 102392 1% /run/user
/dev/sda8 5039616 2948248 1835368 62% /home
/dev/sda2 209715196 203404612 6310584 97% /media/raghu/Data

If a file name is provided as the argument to df command, the filesystem on which the file resides is displayed.

$ df file1.txt
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda8 5039616 2945900 1837716 62% /home

The name of one or more filesystems can also be provided as argument to display the particular filesystems:

$ df /dev/sda{7,8}
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468104 3098980 68% /
/dev/sda8 5039616 2948336 1835280 62% /home

Producing the grand total

The –total option produces a grand total of all filesystems.

$ df –total
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468104 3098980 68% /
udev 1521232 4 1521228 1% /dev
tmpfs 613188 1164 612024 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 8 102392 1% /run/user
/dev/sda8 5039616 2948336 1835280 62% /home
/dev/sda2 209715196 203407688 6307508 97% /media/raghu/Data
total 228608800 212825608 15015192 94%

(Note the last line saying total in the above output)

Including dummy filesystems

-a or –all option includes dummy filesystems (virtual fs like proc, sys etc).

$ df -a
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468104 3098980 68% /
proc 0 0 0 – /proc
sysfs 0 0 0 – /sys
none 0 0 0 – /sys/fs/fuse/connections
none 0 0 0 – /sys/kernel/debug
none 0 0 0 – /sys/kernel/security
udev 1521232 4 1521228 1% /dev
devpts 0 0 0 – /dev/pts
tmpfs 613188 1164 612024 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 8 102392 1% /run/user
/dev/sda8 5039616 2948312 1835304 62% /home
/dev/sda2 209715196 203406664 6308532 97% /media/raghu/Data
binfmt_misc 0 0 0 – /proc/sys/fs/binfmt_misc
gvfsd-fuse 0 0 0 – /run/user/raghu/gvfs

Human Readable Format

With -h options, instead of printing the number of blocks, the data is printed in MBs and GBs. The ’1K-block’ column is replaced with ‘Size’ column.

$ df -h /dev/sda{7,8}
Filesystem Size Used Avail Use% Mounted on
/dev/sda7 9.7G 6.2G 3.0G 68% /
/dev/sda8 4.9G 2.9G 1.8G 62% /home

The -H or –si option is similar to -h, but is uses powers of 1024 and not 1000(as with -h).

$ df -H /dev/sda{7,8}
Filesystem Size Used Avail Use% Mounted on
/dev/sda7 11G 6.7G 3.2G 68% /
/dev/sda8 5.2G 3.1G 1.9G 62% /home

The -B or –block-size=SIZE option can be used to provide custom format for sizes. SIZE may be (or may be an integer optionally followed by) one of following: KB 1000, K 1024, MB 1000*1000, M 1024*1024, and so on for G, T, P, E, Z, Y.

$ df -B2K /dev/sda{7,8}
Filesystem 2K-blocks Used Available Use% Mounted on
/dev/sda7 5039542 3234086 1549456 68% /
/dev/sda8 2519808 1474048 917760 62% /home

$ df -BM /dev/sda{7,8}
Filesystem 1M-blocks Used Available Use% Mounted on
/dev/sda7 9843M 6317M 3027M 68% /
/dev/sda8 4922M 2879M 1793M 62% /home

The -k option is similar to –block-size=1k

$ df -k /dev/sda{7,8}
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468172 3098912 68% /
/dev/sda8 5039616 2948128 1835488 62% /home

The -P option uses the POSIX output format

$ df -P /dev/sda{7,8}
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/sda7 10079084 6468172 3098912 68% /
/dev/sda8 5039616 2948128 1835488 62% /home

Printing inodes and filesystem type

The inodes can be printed with -i or –inodes option.

$ df -i /dev/sda{7,8}
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/sda7 640848 288304 352544 45% /
/dev/sda8 320000 50760 269240 16% /home

Here, total number of inodes, used, free and %age of used inodes are shown respectively.

If you want to print file system types as well, -T or –print-type switch is used

$ df -T
Filesystem Type 1K-blocks Used Available Use% Mounted on
/dev/sda7 ext4 10079084 6468168 3098916 68% /
udev devtmpfs 1521232 4 1521228 1% /dev
tmpfs tmpfs 613188 1164 612024 1% /run
none tmpfs 5120 0 5120 0% /run/lock
none tmpfs 1532964 304 1532660 1% /run/shm
none tmpfs 102400 8 102392 1% /run/user
/dev/sda8 ext4 5039616 2948128 1835488 62% /home
/dev/sda2 fuseblk 209715196 203427116 6288080 98% /media/raghu/Data

Now, suppose you want to print filesystems of a particular type, say ext4 only. The -t or –type=TYPE(ext4 here) option will do this for you.

$ df -t ext4
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468168 3098916 68% /
/dev/sda8 5039616 2948128 1835488 62% /home

$ df -t tmpfs
Filesystem 1K-blocks Used Available Use% Mounted on
tmpfs 613188 1164 612024 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 8 102392 1% /run/user

Similarly, for excluding a particular type of filesystem, use -x or –exclude-type=TYPE.

$ df -x tmpfs
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6468168 3098916 68% /
udev 1521232 4 1521228 1% /dev
/dev/sda8 5039616 2948164 1835452 62% /home
/dev/sda2 209715196 203433404 6281792 98% /media/raghu/Data

$ df -x ext4
Filesystem 1K-blocks Used Available Use% Mounted on
udev 1521232 4 1521228 1% /dev
tmpfs 613188 1164 612024 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 8 102392 1% /run/user
/dev/sda2 209715196 203433404 6281792 98% /media/raghu/Data

Limit listing to local filesystems only

By default, df command displays remote mounted filesystems as well. The -l option limits the listing to local filesystems only.

In order to check usage of this option, first we will mount a remote nfs filesystem.

$ sudo mount 192.168.1.14:/nfs nfs/

$ mount | tail -2
rpc_pipefs on /run/rpc_pipefs type rpc_pipefs (rw)
192.168.1.14:/nfs on /home/raghu/nfs type nfs (rw,vers=4,addr=192.168.1.14,clientaddr=192.168.1.6)

Now we execute the df command:

$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6533664 3033420 69% /
udev 1521232 4 1521228 1% /dev
tmpfs 613188 1172 612016 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 12 102388 1% /run/user
/dev/sda8 5039616 2948364 1835252 62% /home
/dev/sda2 209715196 203556460 6158736 98% /media/raghu/Data
192.168.1.14:/nfs 9547136 3640576 5421568 41% /home/raghu/nfs

And with -l option:

$ df -l
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda7 10079084 6533664 3033420 69% /
udev 1521232 4 1521228 1% /dev
tmpfs 613188 1172 612016 1% /run
none 5120 0 5120 0% /run/lock
none 1532964 304 1532660 1% /run/shm
none 102400 12 102388 1% /run/user
/dev/sda8 5039616 2948388 1835228 62% /home
/dev/sda2 209715196 203565068 6150128 98% /media/raghu/Data

The post Linux df command – Disk Space Usage For Filesystems appeared first on ExpertsLogIn.

Let starts from creating hidden files and folders

How to create hidden files

Just like regular files we can create hidden files with ‘touch’ and ‘vim’. ‘touch’ will create new file and exit but vim create new file and open to modify.

Create single hidden file

[root@srv test]# touch .testfile.txt

Create multiple hidden files

[root@srv test]#touch .file1 .file2 .file3

or

[root@srv test]# vim .test.txt

How to create hidden directory

[root@srv test]# mkdir .hiddndir

Display hidden files

We will use ‘ls’ and ‘ll’ command to display hidden files or directories with options (-a, -A)

[root@srv test]# ls -a

. .. .DIR .hiddndir .test.txt

or

[root@srv test]# ls -al

total 20
drwxr-xr-x. 4 root root 4096 May 3 18:59 .
drwxr-xr-x. 3 root root 4096 May 3 18:52 ..
drwxr-xr-x. 2 root root 4096 May 3 18:59 .DIR
drwxr-xr-x. 2 root root 4096 May 3 18:47 .hiddndir
-rw-r–r–. 1 root root 11 May 3 18:35 .test.txt

[root@srv test]# ll -a

total 20
drwxr-xr-x. 4 root root 4096 May 3 18:59 .
drwxr-xr-x. 3 root root 4096 May 3 18:52 ..
drwxr-xr-x. 2 root root 4096 May 3 18:59 .DIR
drwxr-xr-x. 2 root root 4096 May 3 18:47 .hiddndir
-rw-r–r–. 1 root root 11 May 3 18:35 .test.txt

‘-a’ displays hidden files and directories with current directory (.) and parent directory (..), and ‘-A’ doesn’t display current directory (.) and parent directory (..) as below:

[root@srv test]# ls -A

.DIR .hiddndir .test.txt

or

[root@srv test]# ll -A

total 12
drwxr-xr-x. 2 root root 4096 May 3 18:59 .DIR
drwxr-xr-x. 2 root root 4096 May 3 18:47 .hiddndir
-rw-r–r–. 1 root root 11 May 3 18:35 .test.txt

Hide already created file and directory

[root@srv test]# ll

total 4
-rw-r–r–. 1 root root 0 May 3 19:11 info.txt
drwxr-xr-x. 2 root root 4096 May 3 19:11 nike

let suppose we have already created file info.txt and directory nike and we will hide this file and folder as below

[root@srv test]# mv info.txt .info.txt

[root@srv test]# mv nike .nike

[root@srv test]# ll -A

total 12
-rw-r–r–. 1 root root 0 May 3 19:11 .info.txt
drwxr-xr-x. 2 root root 4096 May 3 19:11 .nike

The post How To Create or Display Hidden Files / Folders in Linux appeared first on ExpertsLogIn.

Check File Attributes

We can check what attributes are set of a file as below:

# lsattr

example:

# lsattr test.txt
- – - – - – - – - test.txt

Change Attributes of File

chattr command which changes the file attributes on a Linux, Let suppose if we will change a file attribute to ‘+i’ attribute. A file with the i attribute cannot be modified: it cannot be deleted or renamed, no link can be created to this file and no data can be written to the file, even root user can’t modify this.

# chattr +i test.txt

# lsattr test.txt
- – - – i – - – - test.txt

If you want to changes in file you need to revert back attributes as below:

# chattr -i test.txt

if you want to allow everybody to just append data to a file and not change already entered data, you can set the append bit as follows:

# chattr +a

example

# lsattr +a test.txt
- – - – a – - – - test.txt

revert back as:

# chattr -a test.txt

There are more options that can use with chattr command

Options

-R Modify directories and their contents recursively.

-V Print modes of attributes after changing them.

-v version Set the file’s version.

Opcodes

+ Add attribute.

- Remove attribute.

= Assign attributes (removing unspecified attributes).

The operator `+’ causes the selected attributes to be added to the existing attributes of the files; `-’ causes them to be removed; and `=’ causes them to be the only attributes that the files have.

Attributes

A Don’t update access time on modify.

a Append only for writing. Can be set or cleared only by a privileged user.

c Compressed.

d No dump.

i Immutable. Can be set or cleared only by a privileged user.

j Journalled file. This is useful only in cases where you are using an ext3 filesystem mounted with the data=”ordered” or data=”writeback” attributes. The data=”journalled” option for the filesystem causes this operation to be performed for all files in the system and makes this option irrelevant.

S Synchronous updates.

s Secure deletion. The contents are zeroed on deletion, and the file cannot be undeleted or recovered in any way.

u Undeletable. This causes a file to be saved even after it has been deleted, so that a user can undelete it later.

The post Chattr Command or Change Attributes of File appeared first on ExpertsLogIn.

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This article is all about changing time zone in MySql. If mysql time zone is not correct, if different from your time zone, you can change it by following steps.

Check current mysql time zone

You should check the current time as below

Login to mysql with root user, run below command

#mysql

or

#mysql -u root -p

Enter root password:

mysql> SELECT NOW();

+———————+
| NOW() |
+———————+
| 2013-05-01 06:43:52 |
+———————+
1 row in set (0.00 sec)

Change Timezone

Stop mysql service

service mysqld stop

shutting down mysqld …………….. OK

Check time_zone tables in mysql db. If it is empty then fill them using below command.

mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root mysql

if you have set root password then:

mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root mysql -p

Execute below command as root user to change timezone

mysql> SET GLOBAL time_zone = timezone;

Example:

mysql> SET GLOBAL time_zone = “Asia/Calcutta”;

The above command will set the timezone to Asia/Calcutta globally. You can change the time zone as per your timezone.

Start mysql service

service mysqld start

starting mysqld …………. OK

The post How To Change Time Zone In MYSQL appeared first on ExpertsLogIn.