for ip in $(seq 1 254); do ping -c 1 10.51.1.$ip>/dev/null; [ $? -eq 0 ] && echo "10.51.1.$ip UP" || : ; done
Now your FTP server is up and running. It is time to add additional users to FTP server so that they can login into account to upload / download files. To add a user called tom and set the password, enter:# adduser -c 'FTP USER Tom' -m tom# passwd tom
Now tom can login using our ftp server. Make sure the following is set in vsftpd.conf
local_enable=YES
Restart the vftpd:# service vsftpd restart
How do I install gnu gcc compiler and related tools such as autoconf, automake, flex, c++ compiler, and bison on a CentOS 7 or Red Hat Enterprise Linux version 7 server?
You can setup a basic development environment with the following packages on a CentOS Enterprise Linux or Red Hat Enterprise Linux version 7:
Open the Terminal app and type the following commands.
Type the following yum command:# yum group list
Sample outputs:
Fig. 01: CentOS / RHEL 7: List Package Groups Command
Type the following [nixcmd name="yum" as root user:# yum group install "Development Tools"
OR$ sudo yum group install "Development Tools"
Sample outputs:
Type the following command to see gcc location:
$ whereis gcc
gcc: /usr/bin/gcc /usr/lib/gcc /usr/libexec/gcc /usr/share/man/man1/gcc.1.gz
Type the following command to see gcc compiler version:
$ gcc --version
gcc (GCC) 4.8.2 20140120 (Red Hat 4.8.2-16)
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Create a file called foo.c as follows:
#include<stdio.h>
int main(void){
printf("Hello World!\n");
return 0;
}
To compile foo.c into foo executable file, type:$ cc foo.c -o foo
To execute foo program, type:
$ ./foo
Hello World!
I recently installed CentOS Linux version 7 or Red Hat Enterprise Linux version 7. How can I restart networking service using command line options? How can I start / stop and restart networking service on a CentOS/RHEL 7 based system?
CentOS 7 / RHEL 7 / Fedora Linux (many other modern distor) uses Systemd. It is a system and service manager for Linux operating systems. In newer distro such as CentOS7/RHEL7 systemd replaces Upstart as the default init system.
In older versions of CentOS or Red Hat Enterprise Linux, you used init scripts located in the /etc/rc.d/init.d/ directory. These init scripts were typically written in Bash, and allowed the system administrator to control the state of services and daemons in their system. In CentOS/RHEL 7, these init scripts have been replaced with service units.
To bring up/down networking service you need to use the network.service.
Use this command to control the systemd system and act as a service manager.
sudo systemctl status network.service
OR
sudo systemctl status network
Sample outputs:
Fig.01: CentOS / RHEL 7 Networking Service Status Command
sudo systemctl restart network.service
OR
sudo systemctl restart network
sudo systemctl start network.service
OR
sudo systemctl start network
sudo systemctl stop network.service
OR
sudo systemctl stop network
Sample outputs:
Animated gif 01: systemctl command in action
The service and chkconfig commands are still available in the system and work as expected, but are only included for compatibility reasons and should be avoided as may be dropped in future release.
Install EPEL Repo on a CentOS and RHEL 7.x
How do I install the extra repositories such as Fedora EPEL repo on a Red Hat Enterprise Linux server version 7.x or CentOS Linux server version 7.x?
You can easily install various packages by configuring a CentOS 7.x or RHEL 7.x system to use Fedora EPEL repos and third party packages. Please note that these packages are not officially supported by either CentOS or Red Hat, but provides many popular packages and apps.
The following instuctions assumes that you are running command as root user on a CentOS/RHEL 7.x system and want to use use Fedora Epel repos.
The command is as follows to download epel release for CentOS and RHEL 7.x using wget command:
cd /tmp
wget https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-2.noarch.rpm
ls *.rpm
To install epel-release-7-2.noarch.rpm, type:
sudo yum install epel-release-7-2.noarch.rpm
Sample outputs:
Loaded plugins: amazon-id, rhui-lb
Examining epel-release-7-2.noarch.rpm: epel-release-7-2.noarch
Marking epel-release-7-2.noarch.rpm to be installed
Resolving Dependencies
--> Running transaction check
---> Package epel-release.noarch 0:7-2 will be installed
--> Finished Dependency Resolution
Dependencies Resolved ================================================================================
Package Arch Version Repository Size================================================================================
Installing:
epel-release noarch 7-2 /epel-release-7-2.noarch 22 k
Transaction Summary================================================================================
Install 1 Package
Total size: 22 k
Installed size: 22 k
Is this ok [y/d/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : epel-release-7-2.noarch 1/1
Verifying : epel-release-7-2.noarch 1/1
Installed:
epel-release.noarch 0:7-2
Complete!
Once installed you should see epel repo using the following yum repolist command$ sudo yum repolist
Sample outputs:
Loaded plugins: amazon-id, rhui-lb
repo id repo name status
epel/x86_64 Extra Packages for Enterprise Linux 7 - x86_64 5,610
rhui-REGION-client-config-server-7/x86_64 Red Hat Update Infrastructure 2.0 Client Configur 2
rhui-REGION-rhel-server-releases/7Server/x86_64 Red Hat Enterprise Linux Server 7 (RPMs) 4,718
repolist: 10,330
To list all available packages under a repo called epel, enter:$ sudo yum --disablerepo="*" --enablerepo="epel" list available
OR$ sudo yum --disablerepo="*" --enablerepo="epel" list available | grep 'package'
OR$ sudo yum --disablerepo="*" --enablerepo="epel" list available | less
Sample outputs:
Fig. 01: List all available packages under a EPEL Repo on a CentOS/RHEL/Fedora Linux
The commands are as follows:
## search it ##
sudo yum search htop
## get more info, if found ##
sudo yum info htop
## install it ##
sudo yum install htop
And, there you have it, a larger number of packages to install from EPEL repo on a CentOS and Red Hat Enterprise Linux (RHEL) version 7.x.
YUM config file, /etc/yum.conf does not contain any proxy definitions ala:
[main]
proxy=http://localhost:8080
proxy_username=put_proxy_user_name_here
proxy_password=put_proxy_user_password_here
August 15, 2014
Samba Server Configuration for CentOS 7 (Guide)
Samba offers file and print services for various clients of Microsoft Windows. It can also integrate with a Windows Server domain. This guide offers the procedure for Samba server configuration in CentOS 7 with anonymous and secured Samba servers.
Samba server CentOS7 also allows for interoperability between Linux/Unix servers as well as Windows-based clients. You need to have one Windows machine to check the CentOS 7 server. The Windows machine must lie on the same workgroup. In order to check the value in the Windows machine, you need to run the “net config workstation” command in cmd prompt.
In order to make windows client reachable, add the entry of your server IP address in the Run terminal.
“notepad C:\Windows\System32\drivers\etc\hosts”
The example values are as follows.
“yum install samba samba-client samba-common”
“mv /etc/samba/smb.conf /etc/samba/smb.conf.bak”
“vi /etc/samba/smb.conf
mkdir -p /samba/anonymous
systemctl enable smb.service
systemctl enable nmb.service
systemctl restart smb.service
systemctl restart nmb.service”
“firewall-cmd –permanent –zone=public –add-service=samba”
“[root@server1 ~]# firewall-cmd –permanent –zone=public –add-service=samba
success
[root@server1 ~]#”
“firewall-cmd –reload”
“ls –l”
“cd /samba
chmod -R 0755 anonymous/
chown -R nobody:nobody anonymous/
ls -l anonymous/”
“chcon -t samba_share_t anonymous/”
“ls -l anonymous/”
“groupadd smbgrp
useradd srijan -G smbgrp
“smbpasswd -a srijan”
“mkdir -p /samba/secured”
“cd /samba
chmod -R 0777 secured/
chcon -t samba_share_t secured/”
“vi /etc/samba/smb.conf”
“systemctl restart smb.service
systemctl restart nmb.service “
“testparm”
“cd /samba
chown -R srijan:smbgrp secured/”
This article should be useful in applying CentOS Samba configuration for anonymous servers.
CentOS / RHEL: Delete Old Yum Repositories and Configuration Files
ow do I delete old yum repositories and configuration files under RHEL 5 or CentOS Linux server?
You can delete old yum repositories and its configuration files from /etc/yum.repos.d/ directory
Type the following commands# cd /etc/yum.repos.d/# ls -l
Sample outputs:
-rw-r--r-- 1 root root 954 Aug 11 2010 epel.repo
-rw-r--r-- 1 root root 1054 Aug 11 2010 epel-testing.repo
-rw-r--r-- 1 root root 561 Dec 14 2010 rhel-debuginfo.repo
-rw-r--r-- 1 root root 222 Dec 14 2010 rhel-source.repo
-rw-r--r-- 1 root root 235 Jan 16 15:27 srpm.repo
To delete epel.repo, enter:# rm epel.repo epel-testing.repo### ***************************** ###### make sure you delete GPG keys also ###### ***************************** #### rm /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL# yum clean all
First, find out repo package name, enter:# rpm -qa | grep epel
Sample outputs:
epel-release-5-4
# yum remove epel-release-5-4# yum clean all
How to Install and Configure OTRS 3.3.X in Centos 6.5 64 bit.
Login as root
Donwload the rpm Package
wget http://ftp.otrs.org/pub/otrs/RPMS/rhel/6/otrs-3.3.5-02.noarch.rpm
Install the rpm Package
yum localinstall -y otrs-3.3.5-02.noarch.rpm
set selinux to permissive mode
setenforce 0
Restart Apache and MySQL
service httpd restart
service mysqld restart
Start OTRS service
service otrs start
Open web browser and add in url your server_ip_or_doamin
http://server_ip_or_domain/otrs/installer.pl
Step 1. Accept the GPL Agreement if you want to install OTRS
Step 2. Give Database details in
Step 3. It will ask for mail record, add the smtp & pop server detail
Step 4. At last it will give username and password, Kindly copy this info
Again Open web browser and add in url your server_ip_or_doamin for Agent Interface
http://server_ip_or_domain/otrs/index.pl
Again Open web browser and add in url your server_ip_or_doamin for Customer Interface
http://server_ip_or_domain/otrs/customer.pl
How to install & configure Tomcat 6 on Centos 6.5
login as root
yum update
yum install -y java
yum install tomcat6 tomcat6-webapps tomcat6-admin-webapps
You can modify default port 8080 to 80 (if required)
vi /usr/share/tomcat6/conf/server.xml
<Connector port="80" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
For tomcat admin modify file
vi /usr/share/tomcat6/conf/tomcat-users.xml
add line
<user username="admin" password="tomcatpass" roles="manager"/>
in between <tomcat-users> & </tomcat-users>
Add permanent at start-up
chkconfig tomcat6 on
Start tomcat
service tomcat6 start
Add port on iptables
iptables -I INPUT -p tcp --dport 8o -j ACCEPT
service iptables save
service iptables restart
Open browser and add url or ip of your server in address bar
click on Tomcat Manager give username and password as you have added on the file tomact-users.xml as admin and tomcatpass
How to install & configure OCSInventory 2.1 Agent on Centos 6.5 64 bit
OCSInventory 2.1 Agent Client Side installation on Linux Centos6
OCSInventory 2.1 Agent install on linux Centos 6.5 64 bit
yum install -y perl-XML-Simple perl-Compress-Zlib perl-Net-IP perl-LWP perl-Digest-MD5 perl-Net-SSLeay
yum install -y perl-Crypt-SSLeay perl-Net-SNMP perl-Proc-Daemon perl-Proc-PID-File perl-Sys-Syslog pciutils smartmontools monitor-edid
wget https://launchpad.net/ocsinventory-unix-agent/stable-2.1/2.1rc1/+download/Ocsinventory-Unix-Agent-2.1rc1.tar.gz
tar zxvf Ocsinventory-Unix-Agent-2.1rc1.tar.gz
cd Ocsinventory-Unix-Agent-2.1rc1
perl Makefile.PL
make
make install
Do you want to configure the agent
press y
Where do you want to write the configuration file?
press 2
Do you want to create the directory /etc/ocsinventory-agent?
press y
Should the old linux_agent settings be imported ?
Type n
What is the address of your ocs server?
Type server name or ip (192.168.1.126)
Do you need credential for the server?
Type n
Do you want to apply an administrative tag on this machine
Type n
Do yo want to install the cron task in /etc/cron.d
Type y
Do you want to create the /var/lib/ocsinventory-agent directory?
Type y
Should I remove the old linux_agent
Type n
Do you want to activate debug configuration option ?
Type y
Do you want to use OCS Inventory NG UNix Unified agent log file ?
Type n
Do you want disable SSL CA verification configuration option (not recommended) ?
Type n
Do you want to set CA certificate chain file path ?
Type n
Do you want to use OCS-Inventory software deployment feature?
Type y
Do you want to use OCS-Inventory SNMP scans feature?
Type y
Do you want to send an inventory of this machine?
Type y
To check the status of server
ocsinventory-agent -f
How to install & configure Nagios 4.x on Centos 6.5
login as root user
yum install httpd php gcc glibc glibc-common gd gd-devel -y
useradd nagios
groupadd nagcmd
usermod -a -G nagcmd nagios
usermod -a -G nagcmd apache
wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-4.0.1.tar.gz
tar zxvf nagios-4.0.1.tar.gz
cd nagios-4.0.1
./configure --with-command-group=nagcmd
make all
make install
make install-init
make install-config
make install-commandmode
make install-webconf
cp -R contrib/eventhandlers/ /usr/local/nagios/libexec/
chown -R nagios:nagios /usr/local/nagios/libexec/eventhandlers
htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
wget https://www.nagios-plugins.org/download/nagios-plugins-1.5.tar.gz
tar xzvf nagios-plugins-1.5.tar.gz
cd nagios-plugins-1.5
./configure --with-nagios-user=nagios --with-nagios-group=nagios
make
make install
SELinux is enforcing then add this line.
semanage fcontext -a -t httpd_sys_content_t /usr/local/nagios/
Set nagios at auto-start & service to start
chkconfig nagios on
chkconfig httpd on
service httpd start
service nagios start
http://localhost/nagios or http://yourserver/nagios
username nagiosadmin
password password
How to install & configure MySql 5.1 on Centos 6.5 64 bit
Login as root
yum update -y
yum install -y mysql mysql-server
Add for auto-restart
chkconfig mysqld on
Start MySql Server
service mysqld start
For secure run this script
mysql_secure_installation
add root password, remove test database and anonymous user
Add port on iptables
iptables -I INPUT -p tcp --dport 3306 -j ACCEPT
service iptables save
service iptables restart
mysql -uroot -pyourpassword
you will be in mysql prompt to quit type exit.
How to install & configure OCSInventory 2.1 Server on Centos 6.5 64 bit
login as root
Download EPEL
wget http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
rpm -ivh epel-release-6-8.noarch.rpm
yum update -y
yum groupinstall -y "Development tools"
yum install -y httpd httpd-devel mod_perl mod_php mod_ssl php-gd php-mysql php-mbstring php perl
yum install -y perl-XML-Simple perl-Compress-Zlib perl-DBI perl-DBD-MySQL perl-Net-IP perl-SOAP-Lite perl-Apache-DBI
yum install -y perl-Apache2-SOAP perl-XML-Entities
yum install -y mysql-server mysql make
Start Service at BootTime
chkconfig httpd on && chkconfig mysqld on
Start Service Iptables add ports 80 for Apache & 3306 for MySql
service iptables start
iptables -I INPUT -m multiport -ptcp --dport 80,3306 -j ACCEPT
service iptables save
service iptables restart
Start Service Apace & MySql
service httpd start && service mysqld start
Login to mysql
mysql -uroot
create database ocsweb;
grant all privileges on ocsweb.* to ocs@localhost identified by "password-2014";
exit
Download OCS SERVER for Linux
wget https://launchpad.net/ocsinventory-server/stable-2.1/2.1/+download/OCSNG_UNIX_SERVER-2.1.tar.gz
tar zxvf OCSNG_UNIX_SERVER-2.1.tar.gz
cd OCSNG_UNIX_SERVER-2.1
sh setup.sh
add enter at ever step
after installation restart apache
service httpd restart
setenforce 0
chmod 775 /usr/share/ocsinventory-reports/ocsreports
chmod 775 /usr/share/ocsinventory-reports/ocsreports/dbconfig.inc.php
http://localhost/ocsreports/
MySQL Login ocs
mySQLpassword password-2014
DatabaseName ocsweb
Mysql HostName localhost
rm /usr/share/ocsinventory-reports/ocsreports/install.php
http://localhost/ocsreports/
user admin
password admin
setenforce 1
***Very Important****
Kindly modify the file and add database password in it.
vi /etc/httpd/conf.d/z-ocsinventory-serv.conf
edit
PerlSetEnv OCS_DB_PWD password-2014
:wq
Go to admin command prompt.
Run below command
# netsh wlan set hostednetwork mode=allow ssid=test key=password
# netsh wlan start hostednetwork
# netsh wlan show hostednetwork
Open > Network and sharing center > change adapter settings >
Local area network Property
Select Sharing tab
FINISHED
Connect your Mobile to your laptop via Wi Fi.
This is a list of the commands used in the Bash shell. Puppy uses the Ash shell up to v 1.0.2 which does not contain all of these commands. From version 1.0.3 (June 2005) these Bash commands are available. |
if you add SHELL=/bin/bash to /etc/profile, rxvt and aterm will run bash automatically
alias : Create an alias
awk : Find and Replace text within file(s)
break : Exit from a loop
builtin : Run a shell builtin
cal : Display a calendar
case : Conditionally perform a command
cat : Display the contents of a file
cd : Change Directory
chgrp : Change group ownership
chmod : Change access permissions
chown : Change file owner and group
chroot : Run a command with a different root directory
cksum : Print CRC checksum and byte counts
clear : Clear terminal screen
cmp : Compare two files
comm : Compare two sorted files line by line
command : Run a command - ignoring shell functions
continue : Resume the next iteration of a loop
cp : Copy one or more files to another location
cron : Daemon to execute scheduled commands
crontab : Schedule a command to run at a later time
csplit : Split a file into context-determined pieces
cut : Divide a file into several parts
date : Display or change the date & time
dc : Desk Calculator
dd : Data Dump - Convert and copy a file
declare : Declare variables and give them attributes
df : Display free disk space
diff : Display the differences between two files
diff3 : Show differences among three files
dir : Briefly list directory contents
dircolors : Colour setup for `ls'
dirname : Convert a full pathname to just a path
dirs : Display list of remembered directories
du : Estimate file space usage
echo : Display message on screen
ed : A line-oriented text editor (edlin)
egrep : Search file(s) for lines that match an extended expression
eject : Eject CD-ROM
enable : Enable and disable builtin shell commands
env : Display, set, or remove environment variables
eval : Evaluate several commands/arguments
exec : Execute a command
exit : Exit the shell
expand : Convert tabs to spaces
export : Set an environment variable
expr : Evaluate expressions
factor : Print prime factors
false : Do nothing, unsuccessfully
fdformat : Low-level format a floppy disk
fdisk : Partition table manipulator for Linux
fgrep : Search file(s) for lines that match a fixed string
find : Search for files that meet a desired criteria
fmt : Reformat paragraph text
fold : Wrap text to fit a specified width.
for : Expand words, and execute commands
format : Format disks or tapes
free : Display memory usage
fsck : Filesystem consistency check and repair.
function : Define Function Macros
gawk : Find and Replace text within file(s)
getopts : Parse positional parameters
grep : Search file(s) for lines that match a given pattern
groups : Print group names a user is in
gzip : Compress or decompress named file(s)
hash : Remember the full pathname of a name argument
head : Output the first part of file(s)
history : Command History
hostname : Print or set system name
id : Print user and group id's
if : Conditionally perform a command
import : Capture an X server screen and save the image to file
info : Help info
install : Copy files and set attributes
join : Join lines on a common field
kill : Stop a process from running
less : Display output one screen at a time
let : Perform arithmetic on shell variables
ln : Make links between files
local : Create variables
locate : Find files
logname : Print current login name
logout : Exit a login shell
lpc : Line printer control program
lpr : Off line print
lprint : Print a file
lprintd : Abort a print job
lprintq : List the print queue
lprm : Remove jobs from the print queue
ls : List information about file(s)
m4 : Macro processor
man : Help manual
mkdir : Create new folder(s)
mkfifo : Make FIFOs (named pipes)
mknod : Make block or character special files
more : Display output one screen at a time
mount : Mount a file system
mtools : Manipulate MS-DOS files
mv : Move or rename files or directories
nice : Set the priority of a command or job
nl : Number lines and write files
nohup : Run a command immune to hangups
passwd : Modify a user password
paste : Merge lines of files
pathchk : Check file name portability
popd : Restore the previous value of the current directory
pr : Convert text files for printing
printcap : Printer capability database
printenv : Print environment variables
printf : Format and print data
ps : Process status
pushd : Save and then change the current directory
pwd : Print Working Directory
quota : Display disk usage and limits
quotacheck : Scan a file system for disk usage
quotactl : Set disk quotas
ram : ram disk device
rcp : Copy files between two machines.
read : read a line from standard input
readonly : Mark variables/functions as readonly
remsync : Synchronize remote files via email
return : Exit a shell function
rm : Remove files
rmdir : Remove folder(s)
rpm : Remote Package Manager
rsync : Remote file copy (Synchronize file trees)
screen : Terminal window manager
sdiff : Merge two files interactively
sed : Stream Editor
select : Accept keyboard input
seq : Print numeric sequences
set : Manipulate shell variables and functions
shift : Shift positional parameters
shopt : Shell Options
shutdown : Shutdown or restart linux
sleep : Delay for a specified time
sort : Sort text files
source : Run commands from a file `.'
split : Split a file into fixed-size pieces
su : Substitute user identity
sum : Print a checksum for a file
symlink : Make a new name for a file
sync : Synchronize data on disk with memory
tac : Concatenate and write files in reverse
tail : Output the last part of files
tar : Tape ARchiver
tee : Redirect output to multiple files
test : Evaluate a conditional expression
time : Measure Program Resource Use
times : User and system times
touch : Change file timestamps
top : List processes running on the system
traceroute : Trace Route to Host
trap : Run a command when a signal is set(bourne)
tr : Translate, squeeze, and/or delete characters
true : Do nothing, successfully
tsort : Topological sort
tty : Print filename of terminal on stdin
type : Describe a command
ulimit : Limit user resources
umask : Users file creation mask
umount : Unmount a device
unalias : Remove an alias
uname : Print system information
unexpand : Convert spaces to tabs
uniq : Uniquify files
units : Convert units from one scale to another
unset : Remove variable or function names
unshar : Unpack shell archive scripts
until : Execute commands (until error)
useradd : Create new user account
usermod : Modify user account
users : List users currently logged in
uuencode : Encode a binary file
uudecode : Decode a file created by uuencode
v : Verbosely list directory contents (`ls -l -b')
vdir : Verbosely list directory contents (`ls -l -b')
watch : Execute/display a program periodically
wc : Print byte, word, and line counts
whereis : Report all known instances of a command
which : Locate a program file in the user's path.
while : Execute commands
who : Print all usernames currently logged in
whoami : Print the current user id and name (`id -un')
xargs : Execute utility, passing constructed argument list(s)
yes : Print a string until interrupted