Temas

Arranque de un sistema HP UX

Posted: March 30th, 2010 | Author: | Filed under: HP UX | No Comments »

HP-UX

Arranque Normal

Este proceso envuelve 3 partes

  • pdc (processor-dependent code)
  • isl (initial system loader)
  • hpux (the secondary system loader)

Después de que se cargan estos 3 elementos la secuencia sigue el proceso init (que ya es conocido en otros Unixes).

Referencia http://www.unixhub.com/docs/hpux/hpux_boot.html


Primer paso para aprender cualquier Unix (un buen editor)

Posted: March 28th, 2010 | Author: | Filed under: Sysadmin | 2 Comments »

Como es bien sabido, todo en unix se maneja en archivos de texto o mejor conocidos como Ascii files, así que si te interesa ser sysadmin lo primero que debes estudiar es un buen editor ya sea vi, emacs o vim. Mi favorito es vi, jeje será porque es el que más domino, pero cualquiera que sea de tu predileccion es bueno en la medida que los domines 😀

Como nota curiosa mi primer libro de unix fué precisamente el de vi editor. Hace bastantes ayeres, por allá del año 2001.


What is a Unix shell?

Posted: March 28th, 2010 | Author: | Filed under: Shell scripting | No Comments »

A Unix shell is a command-line interpreter (see shell) and script host that provides a traditional user interface for the Unix operating system and for Unix-like systems. Users direct the operation of the computer by entering command input as text for a command line interpreter to execute or by creating text scripts of one or more such commands.

The most prominent Unix shells are the Bourne shell, which is the original Unix command line interpreter for system control and user sessions, and the C shell, a shell primarily used for interactive user sessions in the line of Unix-derived operating systems based on the Berkeley Software Distribution (BSD). Both shells have been used as coding base and model for many derivative and work-alike shells with extended feature sets.

My favorite is KSH (Korn shell), second it’s BASH which is the most shell used and it’s basic for linux systems.

Reference: http://en.wikipedia.org/wiki/Unix_shell


What is a shell scripting?

Posted: March 28th, 2010 | Author: | Filed under: Shell scripting | No Comments »

A shell script is a script written for the shell, or command line interpreter, of an operating system. It is often considered a simple domain-specific programming language. Typical operations performed by shell scripts include file manipulation, program execution, and printing text, etc.

Many shell script interpreters double as command line interface, such as the various Unix shells, Windows PowerShell or the MS-DOS COMMAND.COM. Others, such as AppleScript or the graphical Windows Script Host (WScript.exe), add scripting capability to computing environments without requiring a command line interface. Other examples of programming languages primarily intended for shell scripting include DCL and JCL.


HP UX: The elusive question is “How much swap space do I need to configure?”

Posted: March 28th, 2010 | Author: | Filed under: HP UX | No Comments »

I was reading a technical HP UX CSA certification manual.

Chapter Review on Swap Space

The elusive question is “How much swap space do I need to configure?” remains. as always the answer is “It depends” We have looked at why and how swap space is used and configure. I hope we have shed some light on the elsuive dark art or a virtual memory.

If your system is using swap space, the problem is simple; it has breached, at least the lotsfree threshold and vhand as paged-out part of, at least one process.

This is a classic symptom of a memory bottleneck. If the situation persists, you may see a significant increase in system-level processing (vhand executing) as well as a significant increase in system-level IO (vhand posting data pages to the swap area).

I was once asked how to tune a system for best swap space utilization. My answer was simple: Buy more memory or crea secondary swap area space.


Task rated most important according to Linux Professional Institute

Posted: March 28th, 2010 | Author: | Filed under: Linux | No Comments »

Tasks Rated Most Important

1. Check disk space usage
2. List all processes currently running
3. Compress and decompress a file
4. Properly shutdown the system
5. Check free space left on a file system
6. Remove user accounts
7. Change the owner or group of a file
8. Change a user’s forgotten password
9. Change access to a directory
10. Run a process on the background

Reference: http://www.lpi.org


Linux stats

Posted: March 28th, 2010 | Author: | Filed under: Linux | No Comments »

Currently I’m working on getting my LPI certification and reading on the website of LPI, I have read these interesting  Linux stats:

This is a good “why” Linux it’s important in IT industry.

Gender

Male 98.4%
Female 1.6%

Age
Average (median) 27
90% are under 40

English Language Proficiency
Native Speakers 59%
Fluent Non-natives 33%

Continent of Respondents
North America 50%
Europe 33%
Asia 6
Africa 5
Australia 3
South America 2

Country of Respondents (top 10)
1 42%
2 34
3 or more 23
Average (mean): 1.9

Number of Linux Distributors Used
1 42%
2 34
3 or more 23
Average (mean): 1.9

Distributions in Use
Red Hat 79%
Slackware 40
Debian 27
SuSE 19
Caldera 11
Pacific HiTech 2
Other 13
(Totals more than 100% because many people use more than one.)

Where Linux is Used
Home 93%
Work 78%

Self-Rated Linux Competency
Expert 14%
Senior 29%
General 47%
Junior 8%

Years of Linux Professional Experience
Less than 1 14%
1-2 32
3-5 31
6 or more 9

Years of Linux User Experience
Less than 1 8%
1-2 22
3-5 51
6 or more 20

Years of Total Professional IT Technical Support Experience
Less than 1 9%
1-2 20
3-5 38
6-10 22
11 or more 12

Other Operating Systems Experience
Microsoft 80%
Unix Servers 63
Unix Workstations 56
Non-Linux PC Unix 38
VAX/VMS 10
Other 35


The Philosophy of System Administration

Posted: March 28th, 2010 | Author: | Filed under: Sysadmin | No Comments »

I took this from a RH technical manual, it’s a good extract of our daily task as sysadmin.

Although the specics of being a system administrator may change from platform to platform, there
are underlying themes that do not.

These themes make up the philosophy of system administration.
The themes are:

  • Automate everything
  • Document everything
  • Communicate as much as possible
  • Know your resources
  • Know your users
  • Know your business
  • Security cannot be an afterthought
  • Plan ahead
  • Expect the unexpected

HP UX (estabilidad al alcance de las empresas)

Posted: March 25th, 2010 | Author: | Filed under: HP UX | 4 Comments »

En general puedo decir que los sistemas operativos Unix son más estables en comparación con el sistema Windows.

Hay infinidad de sabores de Unix como puedo listar, Linux, HP UX, Solaris, IRIX, AIX, Mac OS,FreeBSD, etc.

Yo soy especialista en HP UX de la empresa HP, pero he usado otros sabores por ejemplo Linux RED HAT (si ya se que pueden criticarlo pero este es el que supo hacerla en cuestiones de soporte y contrator que es lo que a las empresas les interesa, Solaris anteriormente era de la empresa Sun y ahora es de Oracle, Aix de IBM

Cómo mi experiencia ha sido más con HP UX y actualmente Linux tal vez vean más documuentación sobre estos sabores de Unix en esta página.

Desde mi punto de vista creo que hay varias ventajas  que valen la pena recalcar en los sistemas Unix.

  • Estabilidad
  • Disponibilid
  • Confiabilidad

Podria resumir todo eso en un comando “uptime”, puedes tener un servidor en linea sin resetarlo por años, en cambio en windows, eso si que es otra historia, mis colegas Administradores de Windows no me dejaran mentir que cada martes la querida y enriquecida compañia Microsoft libera parches cada martes de la semana, a esto le llamaria yo la industria del bache.

Hay una placque identifica a UNIX que dice live free or die

.

Y las tiras cómicas de Dilbert son también bastante disvertidas y esta haciendo referencia a esta frase unixera.


Espacio Unixero de Lucero

Posted: March 25th, 2010 | Author: | Filed under: Personal | 2 Comments »

En este espacio quiero dar las gracias al GLO Grupo Linux de Occidente

por dejarme hospedar mi sitio.

Compartire en la medida de mis posibilidades de tiempo mi experiencia y tips que les puedan servir para aquellos que esten interesados en estos temas de administración de sistemas.

Si tienes algun comentario o sugerencia, puedes enviarme un correo usando la siguiente forma:

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