How to find a string or text in a file on Linux

How to find a string or text in a file on Linux 

 grep -r --include=\*.forward 'andre'

Remark : Find a sting "andre" on file .forward

How to Postfix Flush the Mail Queue

Under Postfix MTA,

just enter the following command to flush the mail queue:
# postfix flush
OR
# postfix -f

To see mail queue, enter:
# mailq

To list all mail of queue, use one of the following commands.
# postqueue -p

To remove all mail from the queue, enter:
# postsuper -d ALL

To remove all mails in the deferred queue, enter:
# postsuper -d ALL deferred

SSL Library Error: -8181 Certificate has expired on centos server

SSL Library Error: -8181 Certificate has expired
Unable to verify certificate 'Server-Cert'. Add "NSSEnforceValidCerts off" to nss.conf so the server can start until the problem can be resolved


# vim /etc/httpd/conf/httpd.conf

add text "NSSEnforceValidCerts off"

and then save.

For reference How to know certification expiration date
Please execute command below.

# certutil -L -d /etc/httpd/alias -n Server-Cert

Restart service nss
# service nscd restart


Restart Service apache
# service httpd restart



Reff : https://ecl.ntt.com/en/news/2016122801/

how to auto mounting samba from fstab

How to auto mounting samba from fstab

#vim /etc/fstab

put this script :

//192.168.18.6/backup1 /mnt/backup1 cifs username=xxxxx,password=xxxxx 0 0

and then 

# mount -a

check result :

# df -h

How to synchronize file server without password root with SSH keygen on Centos 6

# ssh-keygen

ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 

NB: Please dont put password (Only Enter)

Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
41:71:f3:9b:14:tc:6f:de:fa:m1:05:c5:0d:65:b6:b7 root@svr7.server.co.id
The key's randomart image is:
+--[ RSA 2048]----+
|        o.oo. .+*|
|       . ..o.. ++|
|        .  .o ...|
|         . .oo .o|
|        x  oo. w.|
|            .... |
|             .o  |
|            .  . |
|             ..  |
+-----------------+



Copy id_rsa to server destination

# ssh-copy-id -i ~/.ssh/id_rsa.pub 192.9.18.25




Synchronize Script

# rsync -avz --delete /mnt/test/ root@192.9.18.25:/mnt/test/

script terminal delete file more then 7 day

find -P /home/data/mysql_backup -mtime +7 -delete

How to Mouting NFS Synology on Centos 6.5

#vim /etc/fstab


Put :

//192.9.18.11/Onlinebackup1/ /mnt/backup1   cifs  user=backup,password=xxx,rw,iocharset=utf8 0 0

Esc : wq   for Safe.

Find and remove all file from termilal Linux

# find . -name "*Locky*" -exec rm -rf {} \;

or

# find . -type f -name "*.Locky*" -exec rm -i {} \;

remarks : 

-name "FILE-TO-FIND" : File pattern.
-exec rm -rf {} \; : Delete all files matched by file pattern.
-type f : Only match files and do not include directory name

How to open winmail.dat file on centos

How to open winmail.dat file on centos

#yum install tnef

#tnef winmail.dat

How to open winmail.dat files on Ubuntu / Debian

install tnef
#sudo apt-get install tnef

extract file winmail.dat
#tnef winmail.dat

Install GCC Compiler on centos

Install gcc

[root@localhost /]# yum install gcc gcc-c++


check gcc version

[root@localhost /]# gcc --version
gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
Copyright (C) 2010 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.


Test gcc C compiler with a sample foo.c program

Create a file called test.c :
#vim test.c

add text like this :

#include<stdio.h>
int main(void){
printf("Hello World!\n");
return 0;
}


To compile test.c into foo executable file, type:
# cc test.c -o test


To execute foo program, type:

# ./test
Hello World!

instlal compiler on centos

Setup a basic development environment  on CentOS Enterprise Linux  :

1. autoconf
2. automake
3. binutils
4. bison
5. flex
6. gcc
7. gcc-c++
8. gettext
9. libtool
10. make
11. patch
12. pkgconfig
13. redhat-rpm-config
14. rpm-build
15. rpm-sign
16. libstdc++-devel 
17. libstdc++
18. c++
19. wxGTK-devel
20. wxGTK

#yum install wxGTK-devel wxGTK autoconf automake binutils bison flex gcc gcc-c++ gettext libtool make patch pkgconfig redhat-rpm-config rpm-build rpm-sign libstdc++-devel libstdc++ c++

Remote Desktop (rdesktop) in Redhat/Fedora/CentOS

About Rdesktop

Rdesktop application is use to connect RDP (Remote Desktop Protocol) of any Operating System like Windows XP, Window NT, Windows 2003/2008, Windows Vista and Windows 7 from Linux machine. It’s a client utility for Remote Desktop Protocol (RDP). In this article we are going to view how we can take remote desktop of Windows Terminal using Hostname and IP Address.

Please make sure following points before connecting to remote host.

1. Enable RDP port no. 3389 in Firewall.
2. Enable remote desktop under Windows Operating System.
3. Require at least one user with password.
4. Under MS-Windows desktop >> Right Click on My Computer >> Select properties >> Select Remote tab >> Enable Remote desktop >> Save the changes.

Install rdesktop (Remote Desktop)

#rpm -qa rdesktop

#yum -y install rdesktop


How to use rdesktop with hostname
To connect Windows host from Linux desktop type following command using -u parameter as username (narad) and (ft2) as hostname of my Windows host. To resolve host name make entry at /etc/hosts file if you don’t have DNS Server in your environm


rdesktop -u user_login IP_Host

example :

#rdesktop -u administrator 192.168.1.7

mssql_connect() not working on centos 6.2 / 6.5

server: centos 6.2
PHP Version 5.3.3

had install: freetds; ODBC; php_mssql
selinux was disable
mssql.so was enable in php.ini

for install freetds on centos click here 

if finish restart your server

How to Install Configure FreeTDS on centos 6.5

FreeTDS is a set of libraries for Unix and Linux that allows your programs to natively talk to Microsoft SQL Server and Sybase databases.

Technically speaking, FreeTDS is an open source implementation of the TDS (Tabular Data Stream) protocol used by these databases for their own clients. It supports many different flavors of the protocol and three APIs to access it.
Additionally FreeTDS works with other software such as Perl and PHP, providing access from those languages as well.


Well i will use this to connect my Perl Scripts to SQL Server Databases in CentOS.
Currently in 6.5 using yum, version installed is not working correct with Perl DBD Module. By this reason i need to do this task manually from scratch.

Requirement

RHE EPEL Repository
You must have make and gcc commands installed on your system
1.Install UnixODBC Package

[root@localhost ~]# yum install unixODBC unixODBC-devel

2. Install freeTDS Package

[root@localhost tmp]# wget ftp://ftp.astron.com/pub/freetds/stable/freetds-stable.tgz
[root@localhost tmp]# tar xfvz freetds-stable.tgz
[root@localhost freetds-stable]# cd [your freetds folder]
[root@localhost freetds-stable]# ./configure --prefix=/usr/local/freetds
[root@localhost freetds-stable]# make
[root@localhost freetds-stable]# make install
[root@localhost freetds-stable]# ln -s /usr/local/freetds/etc/freetds.conf /etc/freetds.conf

how to install virtualBox 4.3 on Fedora/CentOS/RHEL

Oracle VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.
VirtualBox supports a large number of guest operating systems:
Windows 3.x
Windows NT 4.0
Windows 2000
Windows XP
Windows Server 2003
Windows Vista
Windows 7
Windows 8
Windows 8.1
DOS
Linux (2.4, 2.6, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11)
Solaris
OpenSolaris
OpenBSD
This guide shows howto install VirtualBox 4.3 (currently 4.3.20) on Fedora 21/20/19/18/17, CentOS 7/6.6/5.11, Red Hat (RHEL) 7/6.6/5.11. This guide uses Virtual Box own yum repositories.
Note: Fedora 16 users can install VirtualBox 4.2, Fedora 15/14 users can install VirtualBox 4.1, Fedora 13 users can install VirtualBox 4.0 and Fedora 12 users can install VirtualBox 3.2.

1. Change to root User
#su -

2. Install Fedora or RHEL Repo Files
#cd /etc/yum.repos.d/


Fedora 21/20/19/18/17/16/15/14/13/12 users
#wget http://download.virtualbox.org/virtualbox/rpm/fedora/virtualbox.repo

CentOS 7/6.6/5.11 and Red Hat (RHEL) 7/6.6/5.11 users
wget http://download.virtualbox.org/virtualbox/rpm/rhel/virtualbox.repo

How to install google chrome on centos 6

Download application from 
# wget http://chrome.richardlloyd.org.uk/install_chrome.sh

Change user access
# chmod +x install_chrome.sh

and then Install application 
# sh install_chrome.sh

Samba Error Multiple connections to a server or shared resource by same user, ..

How to fix samba error on windows client :
"Multiple connections to a server or shared resource by same user, using more than one username, are not allowed. Disconnect all previous connections to the server or shared resource and try again"

Solution
Windows by default stores a cache of all the network drives accessed so that next time when you try to access the same path it will take the credentials from the cache without prompting for username/password again.


In such cases you need to clear the cache. 

How do we do that?
Go to your windows machine and open the cmd prompt

C:\Users\Deepak>net use
New connections will be remembered.
Status       Local     Remote                    Network
-------------------------------------------------------------------------------
OK                     \\192.9.18.6\common        Microsoft Windows Network
The command completed successfully.


As you see above a single cache entry is there in my windows machine for //192.9.18.6, so next time if I try to access this share with some other username/password, I would get the same error.

So we will have to clear this cache

C:\Users\Deepak>net use /delete \\192.168.0.100\IPC$
\\192.168.0.100\IPC$ was deleted successfully.

C:\Users\Deepak>net use
New connections will be remembered.

There are no entries in the list.


or 

If you are using active directory, you can add script ".bat"  on your server for automatically mapping.
add netlogon samba : /var/lib/samba/netlogon/name_logon.bat

with value of file .bat like this  :

net time \\192.9.18.6 /set /yes
net use m: /delete /y
net use m: \\192.9.18.6\common

How to remove all file of same extension files in directory linux

Insert into folder 
and then delete all file of same extention file *.txt

# find . -name "*.txt" -type f -delete

How to install RapidSVN on Centos 6

Download rapidsvn the latest epel-release rpm from
http://dl.fedoraproject.org/pub/epel/6/x86_64/


Install epel-release rpm:
# rpm -Uvh file_name_rapidsvn.rpm


if you are found error: Failed dependencies:
please install library dependencies  using yum search or download from http://pkgs.org/centos-6/epel-x86_64/rapidsvn-0.12.0-3.el6.x86_64.rpm.html


Install rapidsvn rpm package:
# yum install rapidsvn


reff :
http://pkgs.org/centos-6/epel-x86_64/rapidsvn-0.12.0-3.el6.x86_64.rpm.html