Linux Tricks and Techniques

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Friday, 17 November 2017

How to change Hostname permanently in Linux

Linux allow us to change the hostname permanently if required. It could also be changed on temporary basis. Below I am showing you how to change the hostname permanently and on temporary basis. It is very easy task to change hostname in Linux. Please go through the below explanation.


First let me show you the hostname of my server then we will change this hostname temporarily.

So the above image show the current hostname of my server. Now in the below image I am changing this hostname temporarily. It means that once the server is rebooted the hostname will get changed to the previous hostname. 


To make this change permanently we need to edit some files like /etc/hosts and /etc/sysconfig/network. Once we make the entry of this hostname in these files it will not be changed till the time network service is not restarted. Let me show you the same.


Similarly edit /etc/hosts file.


After editing these two files restart /etc/sysconfig/network service and hostname will get changed permanently.

# /etc/sysconfig/network restart.

Thanks





Tuesday, 14 November 2017

How to save output of commands in a file in Linux.

Linux allow us to save all the command outputs in a file while we are working on a Linux server. A command script is used to save these commands output in a file. It is good to use script command to save all necessary command output before stating any major activity. These commands can be any of the Linux command like df -h, fdisk -l, ifconfig -a etc. Here I am sharing on of the same script to save command outputs in a file named logs.txt.




In the above image a file named logs.txt is created using script command, which shows script started file is logs.txt. It means that all the work we will do on this terminal will get save in logs.txt file. To stop these outputs to be saved in logs.txt we need to exit from script as already shown in image. Once we exit from the script we can check all the saved outputs inlogs.txt using vi command.

#vi logs.txt will show the outputs of executed commands in logs.txt file as show below.


So this is how you can save commands output in a file using script command in Linux.

Visit www.linuxtipsonline.com for more articles.

Thanks

Linux Job in Akamai Technologies India Pvt. Ltd.In Bangaluru

AKAMAI TECHNOLOGIES INDIA PRIVATE LIMITED
3 - 8 yrs 
Bengaluru (Bellandur)



Job Description

Akamais Infrastructure Services team is looking for Unix Systems Administrator II who is responsible for operational support of Linux Server Infrastructure and delivering IT Support Services effectively and efficiently

About the Team
Akamais Infrastructure Services team is responsible for provisioning, managing and supporting the Corporate IT infrastructure which is consumed by internal business functions.

As a member of Infrastructure Services team, you are responsible for handling day to day support operations of Linux Servers part of Corporate IT. You will also closely work with all technical towers and different business functions to understand the IT requirements and deliver them in most effective and efficient way

Responsibilities:
On-going administration support of Linux systems and VMWare.
Use system resource utilization and monitoring tools to identify potential problem areas before they result in incidents.
Troubleshoot storage environment problems (connectivity, performance, capacity)
Automate routine administrative and maintenance tasks by scripting the procedures through Shell Scripting, Perl or ansible.
Participate in white hat incidents for problem resolution.
Providing root cause analysis to incidents.
Inventory management of servers and consumables for their technical area
Collaborating with engineering teams for project implementation.
Hardware and software support renewals
Upgrade of essential service like Bind, Infoblox, Netbackup, etc..
Ensure Audit Compliance
Transition tasks from Engineering to operations

Basic Qualifications
Bachelors Degree in Computer Science/Engineering or equivalent.
Overall 7-8 Yrs of experience in the IT Infrastructure Management and Service Delivery
o Minimum 3 Yrs of ITIL based Service Delivery experience
o Minimum 7 Yrs of hand-on technical experience in managing Linux , VMWare and Storage Technologies covering the below
Linux Server Administration, User/computer Account Management and Access rights management
Experience installing, configuring, and maintaining Linux Servers
Experience in troubleshooting of Files system, Disk Management and start-up scripts on Linux servers
Experience in remediating services to infrastructure teams based on vulnerability & policy compliance scans
Maintenance and support of virtualized environments on ESX operating systems
Creation, Management and Configuration of Virtual Machines, Clone and Templates
Manage & troubleshoot issues related to creation of vSwitches, port groups and NIC Teaming
Familiarity with scripting languages like PowerShell, Bash, Perl

Desired Qualifications
Good communication skills, especially with verbal and written English.
Experience in supporting two or more Datacenter site infrastructures



Salary:Not Disclosed by Recruiter

Industry:IT-Software / Software Services

Functional Area:IT Software - Application Programming , Maintenance

Role Category:Admin/Maintenance/Security/Datawarehousing

Role:System Administrator

Employment Type:Permanent Job, Full Time
Keyskills
Linux Administrator Vmware Administrator cluster unix troubleshooting

Desired Candidate Profile
About the job:
Akamais Infrastructure Services team is looking for Unix Systems Administrator II who is responsible for operational support of Linux Server Infrastructure and delivering IT Support Services effectively and efficiently

About the Team
Akamais Infrastructure Services team is responsible for provisioning, managing and supporting the Corporate IT infrastructure which is consumed by internal business functions.

As a member of Infrastructure Services team, you are responsible for handling day to day support operations of Linux Servers part of Corporate IT. You will also closely work with all technical towers and different business functions to understand the IT requirements and deliver them in most effective and efficient way

Responsibilities:
On-going administration support of Linux systems and VMWare.
Use system resource utilization and monitoring tools to identify potential problem areas before they result in incidents.
Troubleshoot storage environment problems (connectivity, performance, capacity)
Automate routine administrative and maintenance tasks by scripting the procedures through Shell Scripting, Perl or ansible.
Participate in white hat incidents for problem resolution.
Providing root cause analysis to incidents.
Inventory management of servers and consumables for their technical area
Collaborating with engineering teams for project implementation.
Hardware and software support renewals
Upgrade of essential service like Bind, Infoblox, Netbackup, etc..
Ensure Audit Compliance
Transition tasks from Engineering to operations

Basic Qualifications
Bachelors Degree in Computer Science/Engineering or equivalent.
Overall 7-8 Yrs of experience in the IT Infrastructure Management and Service Delivery
o Minimum 3 Yrs of ITIL based Service Delivery experience
o Minimum 7 Yrs of hand-on technical experience in managing Linux , VMWare and Storage Technologies covering the below
Linux Server Administration, User/computer Account Management and Access rights management
Experience installing, configuring, and maintaining Linux Servers
Experience in troubleshooting of Files system, Disk Management and start-up scripts on Linux servers
Experience in remediating services to infrastructure teams based on vulnerability & policy compliance scans
Maintenance and support of virtualized environments on ESX operating systems
Creation, Management and Configuration of Virtual Machines, Clone and Templates
Manage & troubleshoot issues related to creation of vSwitches, port groups and NIC Teaming
Familiarity with scripting languages like PowerShell, Bash, Perl

Desired Qualifications
Good communication skills, especially with verbal and written English.
Experience in supporting two or more Datacenter site infrastructures



Education-


UG:B.Tech/B.E. - Computers

PG:Post Graduation Not Required

Doctorate:Doctorate Not Required
Company Profile:


AKAMAI TECHNOLOGIES INDIA PRIVATE LIMITED
Akamai is the leading global service provider for accelerating content and business processes online. Akamai has transformed the Internet from a chaotic network into a predictable, scalable, and secure business platform. Akamai routinely handles 15% of total Internet traffic. The company has created the world's largest and most widely used on-demand distributed computing platform, with more than 14,000 servers in 1,100 networks in 65+ countries.

1,726 organizations have formed trusted relationships with Akamai, improving revenue and reducing costs by maximizing the performance of their online businesses. Akamai's customers include 6 of the top 10 companies from the DJIA, 6 of the top 10 agencies on the Keynote Government 40 index, and many Fortune 500 companies. In India, Akamai's customers include Rediff.com, Sify.com, NDTV, FabMall, Indiatimes, amongst others. The company's strong partner ecosystem includes IBM and EDS, as well as Web-hosting companies, systems integrators, Web developers, software and hardware vendors, and network providers.

Headquartered in Cambridge, Massachusetts, Akamai's industry-leading services, matched with world-class customer care, are used by hundreds of today's most successful enterprises and government agencies around the globe. In India, Akamai's office is located in Bangalore.

Thanks

Sunday, 12 November 2017

How to execute a script at boot using cron in Linux



This article is about to execute a script created by a system admin during reboot of a Linux server. We all know about the cronjob utility of Linux. Cron male this possible for a system admin to execute a script while the system boot. The script may contain any commands outputs or other monitoring codes , all it depends upon the requirement of your setup . Here I am sharing one of the scripts I created and will show you the output of the same once the server is up. This script contains the output of a simple and basic command of Linux i.e “df-h “ and will get automatically save at the desired path of the directory.




In the above image the script reboot.sh will automatically create a file file.txt which will contain the output of df-h command at boot. The permission for the script is 777 you can also set it 755 for root user. Let me show you the script content of reboot.sh
So the above image is the script written in reboot.sh . 

This script will take the output of df -h and will save it in a file file.txt in /root directory. In the previous image you can see that there is no file.txt file exists but once I will reboot the server it will create file.txt in /root directory because this path is given in the script.
Reboot the server and once the server is up check /root directory a file named file.txt would have been created which contains the df –h output of your server.
You can see that a file is been created by name file.txt . Let me show you the output of this command.



File.txt will give you output of df -h during boot. The next important task to execute this script at boot is to make this entry in cronjob in your Linux server. Contab is the utility which allow you to execute the scripts at the desired time. For this script we need to add @reboot in the crontab entry to make this possible for this script execute at boot. The crontab entry is mentioned below.
Also please check the status of cron service and it should be running and keep the cron on at boot as mentioned below.

Thanks




Saturday, 11 November 2017

ORAFACT Solutions Pvt Ltd is hiring Unix/Linux Admin for Bangaluru Location


Unix Administrator-contract to Hire
ORAFACT Solutions Pvt Ltd

3 - 5 yrs 
Bengaluru





Job Description
3-5 years of Unix (solaris/linux) experience. 1-2 years NOC experience.
A successful candidate should have attention to detail, will handle 80%
of escalations that are sent from Tier 1
3-5 years of UNIX experience


Salary:Not Disclosed by Recruiter

Industry:IT-Software / Software Services

Functional Area:Other

Role:Other

Employment Type:Permanent Job, Full Time
Keyskills
Linux Solaris Unix Administration

Desired Candidate ProfilePlease refer to the Job description above
Company Profile:


ORAFACT Solutions Pvt Ltd
ORAFACT is an IT services company specializing in Oracle applications technologies with a unique blend of offerings that straddle across the industry's value chain from Consulting to Education. We Endeavour to deliver real business benefits in a coll



Recruiter Name:Ms. Manjira

Contact Company:ORAFACT Solutions Pvt Ltd

Website:http://WWW.ORAFACT.COM

Monday, 6 November 2017

Linux-Solaris Openings in MBit Computraining Pvt. Ltd. for NCR, Pune Location

Oracle DBA
MBit Computraining Pvt. Ltd.
3 - 6 yrs
Delhi NCR, Pune



Job Description


Required Technical Skill Set

In-depth knowledge and hands on experience of Oracle Administration and build activities.

Technical Competencies

Must Have

Experience with any one of the operating systems among IBM AIX, Linux, SUN Solaris, UNIX operating Systems.
Hands-on experience as an oracle DBA, working with Oracle 9i, 10g and 11g.
Apply PSU patches to various versions of oracle databases rolling for RAC Systems.
Install, configure and troubleshooting on multi node RAC systems on ASM.
Upgrade & Migration of large databases across data Centre.
ASM Instance Creation and troubleshooting.


Preferred Skills
Support several application and support teams with numerous on-going projects.
Third party backup solution configuration (TSM).
Identify performance bottlenecks and propose solutions
Upgrades of databases to 11gR2 Rolling upgrades for RAC environment is a plus.
Good Understanding of oracle Architecture.


Salary:Not Disclosed by Recruiter

Industry:IT-Software / Software Services

Functional Area:IT Software - Application Programming , Maintenance

Role Category:Admin/Maintenance/Security/Datawarehousing

Role:DBA

Employment Type:Permanent Job, Full Time
Keyskills
rac asm oracle dba patching oracle 10g 11g linux unix rman oracle 9i
Desired Candidate ProfilePlease refer to the Job description above
Company Profile:


MBit Computraining Pvt. Ltd.
We are an IT services company with more than 20 years presence in the Industry. We are providing services in IT Staffing , Education and Training, Project Management, Software Solutions etc. Our clients are leading IT companies, MNCs,Central and State Government , PSUs etc.


Recruiter Name:Binod Kumar

Contact Company:Mbit Computraining Pvt Ltd

Address:167/16, 1st Floor, Pratap NagarMayur Vihar -1NEW DELHI,Delhi,India 110091

Website:http://www.mbitindia.net

Telephone:91-11-26562225

Saturday, 4 November 2017

LINUX openings in CONTACTX RESOURCE MANAGEMENT for Mumbai Location


Linux L2

CONTACTX RESOURCE MANAGEMENT
 3 - 7 yrs  
Mumbai




Job Description

We are currently retained by leading MNC / consulting firm to look Linux L2 Admin

o Responsible for mentoring L1 & L2 resources.

o RedHat Certification must

o Good communication skills

Kindly revert on below contact details with your updated resume and following details
Salary:Not Disclosed by Recruiter
Role Category:Programming & Design
Role:Software Developer
Employment Type:Permanent Job, Full Time
Desired Candidate Profile
Please refer to the Job description above

Education-
UG:B.Tech/B.E., BCA, B.Sc
PG:M.Tech, MCA
Company Profile:
CONTACTX RESOURCE MANAGEMENT
Industry
Consultancy Services (Recruitment Consulting/ Staffing Services)


Thanks 

Wednesday, 15 February 2017

NTT DATA Hiring for Linux System Admin

NTT DATA Services
2 - 7 yrs 
Noida



Job Description

Dear Candidate,

Greetings from NTT DATA Services !!

We have an urgent requirement for Linux System Admin professionals for our Noida Location . Please go through the below job details and apply with your updated resume.

An in-depth disciplinary knowledge of Linux (Red Hat, Ubuntu etc) Other UNIX disciplines may be an advantage: IBM AIX, HP-UX 
Knowledge of different hardware architecture, roadmap and implementations. 
Server management including migration and consolidation 
Application systems design and deployments 
Enterprise storage server implementation 
Storage management, virtualization and consolidation 
Linux Cluster (RAC) ) high availability solution implementations 
Disaster recovery planning and executions.
Contribute to the development of new techniques and plans within area of expertise. 
Work on abstract and complex problems requiring evaluation of intangible variables. 
Integrate trends, data and information into plans, deliverables and recommendations. 
Develop innovative and creative output based on interpretation and analysis that improve business performance and contribute to corporate goals and strategic intent. 
Anticipate operational, program, and implementation issues and develops preventative measures. 
Adapt to projects, programs or methods based on customer or business partner feedback. 


If interested kindly apply with the below details:

Total Experience:
Relevant Experience:
Current Company:
Current Location:
Preferred Location:
Current CTC:
Expected CTC:
Notice Period:
Availability for F2F interview process on 18th Feb'2017,Saturday :Y/N


Salary:Not Disclosed by Recruiter

Industry:IT-Software / Software Services

Functional Area:IT Software - Application Programming , Maintenance

Role Category:Programming & Design

Role:Team Lead/Technical Lead
  


Keyskills

Company Profile:

NTT DATA Services
NTT DATA is your Innovation Partner anywhere around the world. With business operations in more than 35 countries, we put emphasis on long-term commitment and combine global reach and local intimacy to provide premier professional services from consulting, system development, business process and IT outsourcing to cloud-based solutions. Visit www.nttdata.com/americas to learn how our consultants, projects, managed services, and outsourcing engagements deliver value for a range of businesses and government agencies.


Thanks

Monday, 13 February 2017

NFS in Linux


NFS is a feature of Linux operating system by which we can share the files or directories from one Linux host to another Linux host. We can also control the policy of read/write operation on a particular file or directory which we want to share. This is very useful feature as sometimes is saves the space on a host machine because the single host can save the file or directory and can be shared on other system.



Let us consider we have two machines with hostname machine1(10.196.11.1) and machine2(10.196.11.2) and we want to share a directory named /project from machine1 to machine2.

That means machine1 is server and machine2 is client for this file sharing. 

The package required for for the NFS is nfs . which we can check by the command using

# rpm -qa | grep nfs

[root@localhost Desktop]# rpm -qa | grep nfs
nfs4-acl-tools-0.3.3-6.el6.x86_64
nfs-utils-lib-1.1.5-6.el6.x86_64
nfs-utils-1.2.3-39.el6.x86_64


If the package is installed then it is ok otherwise we can install the package using YUM utility.

The configuration file of the NFS is /etc/exports and the services required for this sharing are 

1)nfs - should be enabled on both the machines.
2)nfslock
3)portmap

Now let us consider that we want to share /project directory from machine1 to machine2.

At machine1 

[root@localhost Desktop]# mkdir /project
[root@localhost Desktop]# cd /project/
[root@localhost project]# ls
[root@localhost project]# touch file1 file2
[root@localhost project]# ls
file1  file2


Now go to the configuration file of the machine1 and share the directory in that like:

# vi /etc/exports

/project        *(rw,sync)

save the file and restart the nfs service and other services also

# service nfs restart

# service nfslock start

# service portmap start

At Client

# showmount -e 10.196.11.1

the above command will show the shared files or directories from the server 10.196.11.1 and to access these shared directories we need to mount them on client machine.

(nfs, nfslock, portmap should also be started at client also)

# mkdir /nfs

# mount 10.196.11.1:/project /nfs

# cd nfs

will show the files we have created in /project at machine1.

Thanks.













Friday, 10 February 2017

Linux Jobs in NCR


Job Description

Knowledge of CPanel
Worked on Postfix, exim, sendmail servers.Nagios,zenoss server
Apache, nginx web server & DNS functions.
Installation and trouble shooting of Centos, Ubuntu, Redhat, Debian
Troubleshooting of Mysql , Postgresql database server


Salary:INR 2,50,000 - 4,50,000 P.A.

Industry:IT-Software / Software Services

Functional Area:IT Hardware , Technical Support , Telecom Engineering

Role Category:IT Hardware

Role:System Administrator


Keyskills


Desired Candidate Profile : Basic Troubleshooting of Linux OS and network issue.
Installation /troubleshooting of zimbra mail server .
Backup strategies.
Rsync , Scp ,etc.


Company Profile:

Cyfuture India Pvt. Ltd.
Cyfuture is a leading provider of data center, cloud and outsourced support services. The company operates two state-of-the-art, Tier III data centers and 8 BPO delivery centers in India to serve global clients across industries.


Recruiter Name:sneha.bhardwaj@cyfuture.com

Contact Company:Cyber Futuristics India Pvt Ltd

Address:SDF, Block G -13&14,Noida Special Economic Zone (NEPZ)Noida Dadri Road, Phase - 2NOIDA,Uttar Pradesh,India 201305

Website:http://www.cyfuture.com

Telephone:9560193636


Thanks