BASH – Wrappers For qstat In NPACI ROCKS 5.2.2

What is ROCKS?

Rocks Cluster Distribution (originally called NPACI Rocks) is a Linux distribution intended for high-performance computing clusters. It was started by NPACI and the SDSC in 2000, and was initially funded in part by an NSF grant (2000-2007) but is currently funded by the followup NSF grant. Rocks was initially based on the Red Hat Linux distribution, however modern versions of Rocks are now based on CentOS, with a modified Anaconda installer that simplifies mass installation onto many computers. Rocks includes many tools (such as MPI) which are not part of CentOS but are integral components that make a group of computers into a cluster. Installations can be customized with additional software packages at install-time by using special user-supplied CDs (called Roll CDs). The Rolls extend the system by integrating seamlessly and automatically into the management and packaging mechanisms used by base software, greatly simplifying installation and configuration of large numbers of computers. Over a dozen Rolls have been created, including the SGE roll, the Condor roll, the Lustre roll, the Java roll, and the ganglia roll.

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PERL – Retrieving Data From MySQL Databases In Different Servers

Fruit Basket Let us consider the following (hypothetical/real) case: we have a fruit basket with an assortment of fruits in it. Over a period of time, let us suppose we accumulate so much fruit [will they not stink? may be – but that’s a problem beyond the scope of PERL & MySQL] that one basket can no longer hold all the fruits. One possible [and meaningful] way to solve this problem is to introduce another basket and segregate fruits into either one of the two baskets. To make it bit more elegant, we should probably make sure that a given kind of fruit is stored in only one of the baskets. Then, when someone asks us for a fruit – say an Apple – we know which basket contains apples and we can readily pick them out; when someone else asks for an Orange, we can repeat the process; and so on.

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BASH – GZIP or BZIP2?

BASH is a free software Unix shell written for the GNU Project. Its name is an acronym which stands for Bourne-again shell. The name is a pun on the name of the Bourne shell (sh), an early and important UNIX shell written by Stephen Bourne and distributed with Version 7 Unix circa 1978, and the concept of being born again. BASH was created in 1987 by Brian Fox. In 1990 Chet Ramey became the primary maintainer. BASH is the default shell on most GNU/Linux systems as well as on Mac OS X and it can be run on most UNIX-like operating systems. It has also been ported to Microsoft Windows using the POSIX emulation provided by Cygwin, to MS-DOS by the DJGPP project and to Novell NetWare.

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BASH – Wrappers For qstat In NPACI ROCKS

BASH is a free software UNIX shell written for the GNU Project. Its name is an acronym which stands for Bourne-again shell. The name is a pun on the name of the Bourne shell (sh), an early and important UNIX shell written by Stephen Bourne and distributed with Version 7 UNIX circa 1978, and the concept of being born again. BASH was created in 1987 by Brian Fox. In 1990 Chet Ramey became the primary maintainer. BASH is the default shell on most GNU/Linux systems as well as on Mac OS X and it can be run on most UNIX-like operating systems. It has also been ported to Microsoft Windows using the POSIX emulation provided by Cygwin, to MS-DOS by the DJGPP project and to Novell NetWare.

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Expect – Remote SSH Login

Expect is a UNIX automation and testing tool, written by Don Libes as an extension to the Tcl scripting language, for interactive applications such as telnet, ftp, passwd, fsck, rlogin, tip, ssh, and others. It uses UNIX pseudo terminals to wrap up sub-processes transparently, allowing the automation of arbitrary applications that are accessed over a terminal. With Tk, interactive applications can be wrapped in X11 GUIs. Expect has regular expression pattern matching and general program capabilities, allowing simple scripts to intelligently control programs such as telnet, ftp, and ssh, all of which lack a programming language, macros, or any other program mechanism. The result is that Expect scripts provide old tools with significant new power and flexibility.

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BASH – Sum of All File/Folder Sizes

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Read A File, One Line At A Time

Disclaimer

The instructions/steps given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Replace Space In Filenames With Underscore

Disclaimer

The instructions/steps given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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PERL – Password Encryption

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Sum Of All Integers Between Given Two Integers

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Filename Toggle Case

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Center Align A File

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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PERL – Disk Usage Reminder

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

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BASH – Router’s Public IP Address

BASH, AWK and SED

BASH is a free software Unix shell written for the GNU Project. Its name is an acronym which stands for Bourne-again shell. The name is a pun on the name of the Bourne shell (sh), an early and important UNIX shell written by Stephen Bourne and distributed with Version 7 UNIX circa 1978, and the concept of being born again. BASH was created in 1987 by Brian Fox. In 1990 Chet Ramey became the primary maintainer. BASH is the default shell on most GNU/Linux systems as well as on Mac OS X and it can be run on most UNIX-like operating systems. It has also been ported to Microsoft Windows using the POSIX emulation provided by Cygwin, to MS-DOS by the DJGPP project and to Novell NetWare.

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BASH – Login Counter

Disclaimer

The instructions/steps/scripts/methods given below worked for me running CentOS. It may very well work for you on other linux distributions, Red Hat-like or otherwise. Please note that if you decide to use these instructions on your machine, you are doing so entirely at your very own discretion and that neither this site, sgowtham.com, nor its author is responsible for any/all damage – intellectual or otherwise.

Continue reading … “BASH – Login Counter”