How do I display shell command history with date and time under UNIX or Linux operating systems?

If the HISTTIMEFORMAT is set, the time stamp information associated with each history entry is written to the history file, marked with the history comment character. Defining the environment variable as follows

root@linuxforfreshers.com:~$ vim .bash_profile

$ HISTTIMEFORMAT="%d/%m/%y %T "

:wq

Or

root@linuxforfreshers.com:~$  echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bash_profile

root@linuxforfreshers.com:~$ source .bash_profile

Where,

%d – Day

%m – Month

%y – Year

%T – Time

root@linuxforfreshers.com:~$  history

Sample outputs:

986  10/03/1104:31:36 memcached-tool  10.10.28.22:11211 stats

  987  10/03/1104:31:36 w

  988  10/03/1104:31:37 iostat

  989  10/03/1104:31:37 top

  990  10/03/1104:31:37 at

  991  10/03/1104:31:38 atop

  992  10/03/1104:31:40 collectl

  993  10/03/1104:31:41 grep CPU /proc/cpuinfo

  994  10/03/1104:31:45 vmstat 3 100

  995  10/03/1104:31:55 sar -W -f /var/log/sa/sa12

References:

For more info type the following commands:

man bash

help history

man 3 strftime

How to check which port number mysql server is running on linux ?

Method 1:

To find a listener on a port, do this:

root@linuxforfreshers.com:~$netstat -tln | grep 3306

tcp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN     

Or

root@linuxforfreshers.com:~$netstat -tlpn | grep mysql

tcp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN      870/mysqld

Method 2:

root@linuxforfreshers.com:~$grep port /etc/mysql/my.cnf

# One can use all long options that the program supports.

# It has been reported that passwords should be enclosed with ticks/quotes

port                 = 3306

port                 = 3306

Method 3:

Using Mysql Query

root@linuxforfreshers.com:~$  mysql –u username –p password

mysql> SHOW GLOBAL VARIABLES LIKE 'PORT';

+---------------+-------+

| Variable_name | Value |

+---------------+-------+

| port          | 3306  |

+---------------+-------+

how to check mysql server uptime in linux ?

Method 1:

Using command line

root@linuxforfreshers.com:~$mysqladmin  version | grep Uptime

Uptime:                                   30 sec

Method 2:

root@linuxforfreshers.com:~$mysqladmin  status

Uptime: 121  Threads: 1  Questions: 116  Slow queries: 0  Opens: 46  Flush tables: 1  Open tables: 41  Queries per second avg: 0.958

Method 3:

Show MySQL server uptime using a query

root@linuxforfreshers.com:~$ mysql –u username –p password

mysql> SHOW GLOBAL STATUS LIKE 'Uptime';

+---------------+-------+

| Variable_name | Value |

+---------------+-------+

| Uptime        | 223   |

+---------------+-------+

(The uptime is given in seconds)

how to check if mysql server is running or not in linux ?

Method 1:

root@linuxforfreshers.com:~$ service mysql status

Or

root@linuxforfreshers.com:~$ /etc/init.d/mysql status

mysql start/running, process 13749

Method 2:

root@linuxforfreshers.com:~$ps aux | grep mysql

mysql    13749  0.2  1.3 492660 52336 ?        Ssl  13:05   0:38 /usr/sbin/mysqld

Method 3:

root@linuxforfreshers.com:~$netstat -vulntp |grep -i mysql

tcp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN      13749/mysqld    

Method 4:

root@linuxforfreshers.com:~$lsof -i :3306

COMMAND   PID  USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME

mysqld  13749 mysql   10u  IPv4 5037327      0t0  TCP localhost:mysql (LISTEN)

Method 5:

root@linuxforfreshers.com:~$mysqladmin ping

mysqld is alive