Get Linux Server Sends Email Alert on Root Login

This guide is to improve the security of the server, which is exposed to the Internet and possible to get hacked worldwide, it’s best to enable server to automatically send a notification email to predefined email address every time someone logs in as root to the host. To configure the automatic email alert notification to a default email address on each incident of root log on on the server, use the following guide.
  1. Login to the server via SSH using as root ID.
  2. Ensure that you’re at home directory of root. The open up the .bash_profile for editing using vi by typing one of the following commands at command shell line:vi .bash_profile
  3. Scroll down to the end of the file and add the following line:
    echo 'ALERT - Root Shell Access on:' `date` `who` | mail -s "Alert: Root... 						

Remove Duplicate Rows from a Table in SQL Server

Firstly, we will create a table, where we will insert some duplicate rows to understand the topic properly. Create a table called ATTENDANCE by using the following code: CREATE TABLE [dbo].[ATTENDANCE]( [EMPLOYEE_ID] [varchar](50) NOT NULL, [ATTENDANCE_DATE] [date] NOT NULL ) ON [PRIMARY] Now insert some data into this table. INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A001',CONVERT(DATETIME,'01-01-11',5)) INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A001',CONVERT(DATETIME,'01-01-11',5)) INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A002',CONVERT(DATETIME,'01-01-11',5)) INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A002',CONVERT(DATETIME,'01-01-11',5)) INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A002',CONVERT(DATETIME,'01-01-11',5)) INSERT INTO dbo.ATTENDANCE (EMPLOYEE_ID,ATTENDANCE_DATE)VALUES ('A003',CONVERT(DATETIME,'01-01-11',5)) After inserting the data, check the data of the below table. If we grouped the employee_id and attendance_date, then A001 and A002 become duplicates. EMPLOYEE_ID ATTENDANCE_DATE A001 2011-01-01 A001 2011-01-01 A002 2011-01-01 A002 2011-01-01 A002 2011-01-01 A003 2011-01-01 So how can we delete those duplicate data? Solution First, insert an identity column in that table by using the following code: ALTER TABLE dbo.ATTENDANCE ADD AUTOID INT IDENTITY(1,1) Now the table data will be like the following table: EMPLOYEE_ID ATTENDANCE_DATE AUTOID A001 2011-01-01 1 A001 2011-01-01 2 A002...

How to change VNC Server password on Linux

To change VNC Password on Linux You can either connect to the machine remotely over an ssh program like putty or you can do this directly from the terminal. Open up a command prompt for the user that you have vnc server running as. Then type vncpasswd You will then be prompted to enter a new password twice. Choose your new vnc server password and then restart the vncserver service using the following command. service vncserver restart The above commands work when run as the root user on Centos but should work similarly on most other variation of Linux....

Ever been Hacked and now you can’t delete the file…Operation not permitted

You can check the file and ownership permissions as well as if the file is set to immutable with these commands in root SSH: ls -lah /home/username/public_html/pathtofile lsattr /home/username/public_html/pathtofile The first command will show the file and ownership permissions. If they are 000 or root:root, the root user should still be able to remove the file regardless with this command: cd /home/username/public_html/pathtofolder rm filename People can really get into trouble by running rm commands without ensuring they are at the correct directory path for the removal. Next, the "lsattr" command above, the second one, will show if there are any attributes set on the file. If you see a -i on the lsattr command, then run this command to unset that attribute: chattr -i /home/username/public_html/pathtofile This will remove that immutable file attribute. What immutable does would be preventing changing and removing a file. If...

Killing zombie process

Zombie process is an inactive computer process, according to wikipedia article, "...On Unix operating systems, a zombie process or defunct process is a process that has completed execution but still has an entry in the process table, allowing the process that started it to read its exit status. In the term's colorful metaphor, the child process has died but has not yet been reaped..." So how do I find out zombie process? Use top or ps command: # top OR # ps aux | awk '{ print $8 " " $2 }' | grep -w Z Output: Z 4104 Z 5320 Z 2945 How do I kill zombie process? You cannot kill zombies, as they are already dead. But if you have too many zombies then kill parent process or restart service. You can kill zombie process using PID obtained from any one of the above command....

How to Unprotect an excel sheet without password

THis document will tel you how to unprotect an excel spread sheet without having the password In case of a password protect worksheet you are unable to Edit the data on the Excel Sheet. If you do not Remember the Password or do not know the password to unprotect the sheet just follow the below simple steps. excel1 Press ALT + F11 or click on View Code in Developers Tabs Excel2 In the Above White Space Enter the below Code. Do not change the code just copy paste:
Sub PasswordBreaker()
    'Breaks worksheet password protection.
    Dim i As Integer, j As Integer, k As Integer
    Dim l As Integer, m As Integer, n As Integer
    Dim i1 As Integer, i2 As Integer, i3 As...