Category Archives: Featured
Learn to use awk for text and data extraction, data processing, validation, generate reports for analysis, automation with with the help of examples of if else , compare & arrays plus regular expressions & built in operational variables, meaning, examples &command syntax.
Application monitoring is a very important aspect of a project but unfortunately not much attention is paid to develop the effective monitoring while the projects are still movingh to completions. Once project is complete & live lack of proper monitoring costs in terms of downtime when support persons are not aware if application is having some problems or application not working at all.
Learn about Linux and Unix date & time formating with the help of simple explanation and added example. Date command in Unix & Linux is used to format date as well as time. First portion of this article covers Date function and the second portion has the time function covered.
How to configure passwordless ssh &sftp access in Unix & Linux systems? Follow these simple steps with examples with a basic troubleshooting section at the end. sftp uses underlaying ssh access for authentication and after you establish passwordless ssh access you will have passwordless sftp access as well.
This a real life example of configuring passwordless access for two users . The user ‘web’ in this case needs a secure password less access to another user james in a server ‘devserver’
This is a Unix Tutorial where you can learn Unix OS Basics to get started with UNIX and Linux operating systems and covers Unix Directory structure , Unix Commads and Unix Shells
Setting up cron jobs in Unix, Solaris & Linux
cron is a unix, solaris, Linux utility that allows tasks to be automatically run in the background at regular intervals by the cron daemon.
Learn about the Unix commands with their usages and examples.
This Unix command tutorial introduces you with some of the most popular and useful commands used in nix operating system to get you started with Unix.
All Unix OS comes with online manual system, man, which can be used used as ,man
Learn about the default text editor, vi, pronounced as ”vee eye”, in Unix, Linux and other Unix like systems. A short, concise vi editor quick reference lets you get started with vi today. Explains vi editor mode & many common vi commands with examples for editing in vi.
Unix and Linux backup and restore can be done using backup commands tar, cpio ufsdump, dump and restore. Though these commands may be sufficient for small setups in order to take a enterprise backup you have to go in for some custom backup and restore solutions like Symatic netbackup, EMC networker or Amanda.
Any backup solution using these commands depends on the type of backup you are taking as these backup commands offers different capabilities.
DNS troubleshooting , this article describes some of the common dns problems and their solutions.
First phase of article describes dns errors relating to configuration , server setup and its basic functionality . Second phase talks about the nslookup related errors when the dns servers seems to be working correctly but names resolution fail .
Learn about fsck modes, fsck phases & fsck errors messages, their explanation along with some suggested course of action to successfully repair unix, Linux file system.
fsck, file system consistency check, is a system utilty in Unix, Linux and other Unix like systems for checking and repairing file system inconsistencies.
File system can become inconsistent due to several reasons and the most common is abnormal shutdown due to hardware failure, power failure or switching off the system without proper shutdown. Due to these reasons the superblock in a file system is not updated and has mismatched information relating to system data blocks, free blocks and inodes.
fsck in Linux
fsck in this document is refered with reference to ufs file system but it can be used in Linux systems as
fsck -t ext2 /dev/sda3
it returns with any of the followig code
0 – No errors
1 – File system errors corrected
2 – System should be rebooted
4 – File system errors left uncorrected
8 – Operational error
16 – Usage or syntax error
32 – Fsck canceled by user request
128 – Shared library error
fsck checks the file systems defined in /etc/fstab in Linux and /etc/vfstab in Unix systems