Chapter 1. Overview / 1.4. Heartbeat Cluster Components | ||||
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 | 1.3. Cluster Configurations | 1.5. Architecture |  | |
Chapter 1. Overview / 1.4. Heartbeat Cluster Components | ||||
|---|---|---|---|---|
| 1.3. Cluster Configurations | 1.5. Architecture | | |
The following components make up a Heartbeat version 2 cluster:
From 2 to 16 Linux servers, each containing at least one local disk device.
Heartbeat software running on each Linux server in the cluster.
Optional: A shared disk subsystem connected to all servers in the cluster.
Optional: High-speed Fibre Channel cards, cables, and switch used to connect the servers to the shared disk subsystem.
At least two communications mediums over which Heartbeat servers can communicate. These currently include Ethernet (mcast, ucast, or bcast) or Serial.
A STONITH device. A STONITH device is a power switch which the cluster uses to reset nodes that are considered dead. Resetting non-heartbeating nodes is the only reliable way to ensure that no data corruption is performed by nodes that hang and only appear to be dead.
See The High-Availability Linux Project for more information on STONITH.
