PDF de programación - Clustering y Alta Disponibilidad en GNU/Linux - Utilización y Administración avanzada de sistemas GNU/Linux y aplicaciones Software Libre para estudiantes universitarios

Utilización y Administración avanzadas
de sistemas GNU/Linux y aplicaciones

Software Libre para estudiantes

universitarios

Clustering y Alta Disponibilidad en GNU/Linux

Josá Angel de Bustos Pérez

Utilización y Administración avanzadas de sistemas GNU/Linux y aplicaciones Software Libre para
estudiantes universitariosClustering y Alta Disponibilidad en GNU/Linux
por Josá Angel de Bustos Pérez

Copyright (c) 2.007 José Angel de Bustos Pérez <[email protected]>.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy
of the license is included in the section entitled "GNU Free Documentation License".

Tabla de contenidos

1. Clustering ...............................................................................................................................................1
1.1. Que es el clustering? ...................................................................................................................1
1.2. Tipos de cluster ...........................................................................................................................1
1.3. High Performance Cluster...........................................................................................................1
1.3.1. Ventajas...........................................................................................................................2
1.3.2. Inconvenientes ................................................................................................................2
1.4. Cluster Activo / Pasivo................................................................................................................2
1.4.1. Ventajas...........................................................................................................................2
1.4.2. Inconvenientes ................................................................................................................2
1.5. Cluster Activo / Activo................................................................................................................2
1.5.1. Ventajas...........................................................................................................................2
1.5.2. Inconvenientes ................................................................................................................3
1.6. Grid Computing ..........................................................................................................................3
1.6.1. Ventajas...........................................................................................................................3
1.6.2. Inconvenientes ................................................................................................................3
2. Arquitectura de Clustering...................................................................................................................4
2.1. Alta disponibilidad......................................................................................................................4
2.1.1. Los famosos 9s ...............................................................................................................4
2.1.2. Bonding ..........................................................................................................................5
2.1.3. Almacenamiento.............................................................................................................5
2.2. Escalabilidad ...............................................................................................................................6
2.3. Funcionamiento de un cluster .....................................................................................................6
2.3.1. Balanceador de carga......................................................................................................7
2.3.2. Sistema para la detección de fallos en los nodos del cluster ..........................................7
2.3.3. Servicio a clusterizar ......................................................................................................7
2.3.4. Recursos del cluster........................................................................................................7
2.3.5. Fencing ...........................................................................................................................8
3. Balanceo de Carga .................................................................................................................................9
3.1. Balanceadores hardware..............................................................................................................9
3.1.1. Ventajas...........................................................................................................................9
3.1.2. Inconvenientes ................................................................................................................9
3.2. Balanceadores software.............................................................................................................10
3.2.1. Ventajas.........................................................................................................................10
3.2.2. Inconvenientes ..............................................................................................................10
3.3. Balanceo en DNS ......................................................................................................................10
3.4. Linux Virtual Server - LVS .......................................................................................................11
3.4.1. Virtual Server mediante NAT........................................................................................12
3.4.2. Virtual Server mediante IP Tunneling ..........................................................................14
3.4.3. Virtual Server mediante Direct Routing .......................................................................16
3.4.4. El problema del ARP ....................................................................................................18
3.4.5. Algoritmos de planificación en LVS .............................................................................19
3.4.6. ipvsadm.........................................................................................................................21
3.4.7. Alta disponibilidad en los balanceadores con keepalived ............................................22
3.4.8. Configuración de keepalived ........................................................................................25

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4. Detección de fallos en los nodos del cluster........................................................................................29
4.1. Heartbeat ...................................................................................................................................29
4.2. Disco de quorum .......................................................................................................................29
5. Fencing..................................................................................................................................................30
6. Otras soluciones libres para Clustering.............................................................................................31
6.1. Heartbeat ...................................................................................................................................31
6.2. Mon ...........................................................................................................................................31
6.3. Fake ...........................................................................................................................................31
6.4. ldirectord ...................................................................................................................................31
6.5. Kimberlite .................................................................................................................................31
6.6. Ultramonkey..............................................................................................................................31
6.7. Red Hat Cluster Suite................................................................................................................32
A. GNU Free Documentation License....................................................................................................33
A.1. PREAMBLE ............................................................................................................................33
A.2. APPLICABILITY AND DEFINITIONS ................................................................................33
A.3. VERBATIM COPYING...........................................................................................................34
A.4. COPYING IN QUANTITY .....................................................................................................35
A.5. MODIFICATIONS...................................................................................................................35
A.6. COMBINING DOCUMENTS.................................................................................................37
A.7. COLLECTIONS OF DOCUMENTS ......................................................................................37
A.8. AGGREGATION WITH INDEPENDENT WORKS..............................................................38
A.9. TRANSLATION ......................................................................................................................38
A.10. TERMINATION.......................................................................