simple commands

Introduction to LINUX (Basic Commands) [root@localhost ~]# hostname localhost.localdomain [root@localhost ~]# ifconfig  eth0      Link encap:Ethernet  HWaddr 00:0C:29:63:46:BD inet addr:172.16.28.145  Bcast:172.16.28.255  Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fe63:46bd/64 Scope:Link UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1 RX packets:2332 errors:0 dropped:0 overruns:0 frame:0 TX packets:1455 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:257468 (251.4 KiB)  TX bytes:192203 (187.6 KiB) … Continue reading simple commands

shell-scripts

Shell-Scripting: First look how to print the text using script [root@shellscripting ~]# touch one [root@shellscripting ~]# cat > one echo "Hello every one Thanks for reading" [root@shellscripting ~]# sh one  Hello every one Thanks for reading [root@shellscripting ~]# bash one Hello every one Thanks for reading ----------------------------------------------------------------------------------------------------- [root@shellscripting ~]# touch second [root@shellscripting ~]# [root@shellscripting ~]# … Continue reading shell-scripts

important commands

cut,sort,uniq.sed.awk commands [root@rhel6-client1 ~]# cat cutcommand  hello now we are gojng to explain cut command this is the first line of our practise seond line of our practise session third line will be this fourth line  consists of this data like this we can practise [root@rhel6-client1 ~]# cut -d " " -f1 cutcommand hello this … Continue reading important commands

monitoring commands

Top Command   Top Command: As a Linux system administrator, top command is a frequently used command and our daily tasks we used multiple times this commands to view resource utilization by processes on server. This command helps us to find which process is utilizing what resources of system. Result Row #1: Row 1 results … Continue reading monitoring commands

advanced file-permissions

Advanced File Permissions(sgid-suid-stickybit,chattr) SUID ( setuid ) :- If SUID bit is set on a file and a user executed it. The process will have the same rights as the owner of the file being executed. For example: passwd command have SUID bit enabled. When a normal user change his password this script update few … Continue reading advanced file-permissions

job-scheduling

Linux crontab is similar to windows task schedules. Crontab are very useful for routine tasks like scheduling system scanning, daily backups etc. Crontab executes jobs automatically in back-end on specified time interval. For scheduling one time tasks you can use at command in Linux. Linux crontab have six fields. 1-5 fields denotes time and 6’th … Continue reading job-scheduling

lvm

LVM [root@LVM ~]# rpm -qa | grep lvm lvm2-libs-2.02.118-2.el6.x86_64 lvm2-2.02.118-2.el6.x86_64 mesa-private-llvm-3.4-3.el6.x86_64 -------------------------------------------------------------------------------- [root@LVM ~]# fdisk /dev/sda WARNING: DOS-compatible mode is deprecated. It's strongly recommended to switch off the mode (command 'c') and change display units to sectors (command 'u'). Command (m for help): p Disk /dev/sda: 64.4 GB, 64424509440 bytes 255 heads, 63 sectors/track, 7832 … Continue reading lvm

Disk Partitioning and Mounting File System

[root@partitioning ~]# lsblk  NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT loop0    7:0    0  3.6G  1 loop /mnt/iso sda      8:0    0   20G  0 disk ├─sda1   8:1    0  300M  0 part /boot └─sda2   8:2    0 17.7G  0 part / sr0     11:0    1 1024M … Continue reading Disk Partitioning and Mounting File System

filepermissions

Introduction Linux is a multi-user OS that is based on the Unix concepts of file ownership and permissions to provide security, at the file system level. If you are planning improving your Linux skills, it is essential that have a decent understanding of how ownership and permissions work. There are many intricacies when dealing with … Continue reading filepermissions