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#
# AUTHOR <EMAIL@ADDRESS>, YEAR.
#
msgid ""
msgstr ""
"Project-Id-Version: 0\n"
"POT-Creation-Date: 2018-05-14 18:03-0500\n"
"PO-Revision-Date: 2018-05-14 18:03-0500\n"
"Last-Translator: Automatically generated\n"
"Language-Team: None\n"
"MIME-Version: 1.0\n"
"Content-Type: application/x-publican; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
#. Tag: title
#, no-c-format
msgid "Read-Me-First"
msgstr ""
#. Tag: title
#, no-c-format
msgid "The Scope of this Document"
msgstr ""
#. Tag: para
#, no-c-format
msgid "This document is intended to be an exhaustive reference for configuring Pacemaker."
msgstr ""
#. Tag: para
#, no-c-format
msgid "To achieve this, it focuses on the XML syntax used to configure the CIB. For those that are allergic to XML, multiple higher-level front-ends (both command-line and GUI) are available. These tools will not be covered at all in this document <footnote><para> I hope, however, that the concepts explained here make the functionality of these tools more easily understood. </para></footnote>."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Users may be interested in other parts of the <ulink url=\"https://www.clusterlabs.org/pacemaker/doc/\">Pacemaker documentation set</ulink>, such as <emphasis>Clusters from Scratch</emphasis>, a step-by-step guide to setting up an example cluster, and <emphasis>Pacemaker Administration</emphasis>, a guide to maintaining a cluster."
msgstr ""
#. Tag: title
#, no-c-format
msgid "What Is <emphasis>Pacemaker</emphasis>?"
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Pacemaker</emphasis> is a high-availability <emphasis>cluster resource manager</emphasis> — software that runs on a set of hosts (a <emphasis>cluster</emphasis> of <emphasis>nodes</emphasis>) in order to minimize downtime of desired services (<emphasis>resources</emphasis>). <footnote><para> <emphasis>Cluster</emphasis> is sometimes used in other contexts to refer to hosts grouped together for other purposes, such as high-performance computing (HPC), but Pacemaker is not intended for those purposes. </para></footnote>"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker’s key features include:"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Detection of and recovery from node- and service-level failures"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Ability to ensure data integrity by fencing faulty nodes"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Support for one or more nodes per cluster"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Support for multiple resource interface standards (anything that can be scripted can be clustered)"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Support (but no requirement) for shared storage"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Support for practically any redundancy configuration (active/passive, N+1, etc.)"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Automatically replicated configuration that can be updated from any node"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Ability to specify cluster-wide relationships between services, such as ordering, colocation and anti-colocation"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Support for advanced service types, such as <emphasis>clones</emphasis> (services that need to be active on multiple nodes), <emphasis>stateful resources</emphasis> (clones that can run in one of two modes), and containerized services"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Unified, scriptable cluster management tools"
msgstr ""
#. Tag: title
#, no-c-format
msgid "Fencing"
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis>Fencing</emphasis>, also known as <emphasis>STONITH</emphasis> (an acronym for Shoot The Other Node In The Head), is the ability to ensure that it is not possible for a node to be running a service. This is accomplished via <emphasis>fence devices</emphasis> such as intelligent power switches that cut power to the target, or intelligent network switches that cut the target’s access to the local network."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker represents fence devices as a special class of resource."
msgstr ""
#. Tag: para
#, no-c-format
msgid "A cluster cannot safely recover from certain failure conditions, such as an unresponsive node, without fencing."
msgstr ""
#. Tag: title
#, no-c-format
msgid "Cluster Architecture"
msgstr ""
#. Tag: para
#, no-c-format
msgid "At a high level, a cluster can viewed as having these parts (which together are often referred to as the <emphasis>cluster stack</emphasis>):"
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Resources:</emphasis> These are the reason for the cluster’s being — the services that need to be kept highly available."
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Resource agents:</emphasis> These are scripts or operating system components that start, stop, and monitor resources, given a set of resource parameters. These provide a uniform interface between Pacemaker and the managed services."
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Fence agents:</emphasis> These are scripts that execute node fencing actions, given a target and fence device parameters."
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Cluster membership layer:</emphasis> This component provides reliable messaging, membership, and quorum information about the cluster. Currently, Pacemaker supports <ulink url=\"http://www.corosync.org/\">Corosync</ulink> as this layer."
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Cluster resource manager:</emphasis> Pacemaker provides the brain that processes and reacts to events that occur in the cluster. These events may include nodes joining or leaving the cluster; resource events caused by failures, maintenance, or scheduled activities; and other administrative actions. To achieve the desired availability, Pacemaker may start and stop resources and fence nodes."
msgstr ""
#. Tag: para
#, no-c-format
msgid "<emphasis role=\"strong\">Cluster tools:</emphasis> These provide an interface for users to interact with the cluster. Various command-line and graphical (GUI) interfaces are available."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Most managed services are not, themselves, cluster-aware. However, many popular open-source cluster filesystems make use of a common <emphasis>Distributed Lock Manager</emphasis> (DLM), which makes direct use of Corosync for its messaging and membership capabilities and Pacemaker for the ability to fence nodes."
msgstr ""
#. Tag: title
#, no-c-format
msgid "Example Cluster Stack"
msgstr ""
#. Tag: title
#, no-c-format
msgid "Pacemaker Architecture"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker itself is composed of multiple daemons that work together:"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemakerd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-attrd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-based"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-controld"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-execd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-fenced"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-schedulerd"
msgstr ""
#. Tag: title
#, no-c-format
msgid "Internal Components"
msgstr ""
#. Tag: para
#, no-c-format
msgid "The Pacemaker master process (pacemakerd) spawns all the other daemons, and respawns them if they unexpectedly exit."
msgstr ""
#. Tag: para
#, no-c-format
msgid "The <emphasis>Cluster Information Base</emphasis> (CIB) is an <ulink url=\"https://en.wikipedia.org/wiki/XML\">XML</ulink> representation of the cluster’s configuration and the state of all nodes and resources. The <emphasis>CIB manager</emphasis> (pacemaker-based) keeps the CIB synchronized across the cluster, and handles requests to modify it."
msgstr ""
#. Tag: para
#, no-c-format
msgid "The attribute manager (pacemaker-attrd) maintains a database of attributes for all nodes, keeps it synchronized across the cluster, and handles requests to modify them. These attributes are usually recorded in the CIB."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Given a snapshot of the CIB as input, the <emphasis>scheduler</emphasis> (pacemaker-schedulerd) determines what actions are necessary to achieve the desired state of the cluster."
msgstr ""
#. Tag: para
#, no-c-format
msgid "The <emphasis>local executor</emphasis> (pacemaker-execd) handles requests to execute resource agents on the local cluster node, and returns the result."
msgstr ""
#. Tag: para
#, no-c-format
msgid "The <emphasis>fencer</emphasis> (pacemaker-fenced) handles requests to fence nodes. Given a target node, the fencer decides which cluster node(s) should execute which fencing device(s), and calls the necessary fencing agents (either directly, or via requests to the fencer peers on other nodes), and returns the result."
msgstr ""
#. Tag: para
#, no-c-format
msgid "The <emphasis>controller</emphasis> (pacemaker-controld) is Pacemaker’s coordinator, maintaining a consistent view of the cluster membership and orchestrating all the other components."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker centralizes cluster decision-making by electing one of the controller instances as the <emphasis>Designated Controller</emphasis> (<emphasis>DC</emphasis>). Should the elected DC process (or the node it is on) fail, a new one is quickly established. The DC responds to cluster events by taking a current snapshot of the CIB, feeding it to the scheduler, then asking the executors (either directly on the local node, or via requests to controller peers on other nodes) and the fencer to execute any necessary actions."
msgstr ""
#. Tag: title
#, no-c-format
msgid "Old daemon names"
msgstr ""
#. Tag: para
#, no-c-format
msgid "The Pacemaker daemons were renamed in version 2.0. You may still find references to the old names, especially in documentation targeted to version 1.1."
msgstr ""
#. Tag: entry
#, no-c-format
msgid "Old name"
msgstr ""
#. Tag: entry
#, no-c-format
msgid "New name"
msgstr ""
#. Tag: para
#, no-c-format
msgid "attrd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "cib"
msgstr ""
#. Tag: para
#, no-c-format
msgid "crmd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "lrmd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "stonithd"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker_remoted"
msgstr ""
#. Tag: para
#, no-c-format
msgid "pacemaker-remoted"
msgstr ""
#. Tag: title
#, no-c-format
msgid "Node Redundancy Designs"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker supports practically any <ulink url=\"https://en.wikipedia.org/wiki/High-availability_cluster#Node_configurations\">node redundancy configuration</ulink> including <emphasis>Active/Active</emphasis>, <emphasis>Active/Passive</emphasis>, <emphasis>N+1</emphasis>, <emphasis>N+M</emphasis>, <emphasis>N-to-1</emphasis> and <emphasis>N-to-N</emphasis>."
msgstr ""
#. Tag: para
#, no-c-format
msgid "Active/passive clusters with two (or more) nodes using Pacemaker and <ulink url=\"https://en.wikipedia.org/wiki/Distributed_Replicated_Block_Device:\">DRBD</ulink> are a cost-effective high-availability solution for many situations. One of the nodes provides the desired services, and if it fails, the other node takes over."
msgstr ""
#. Tag: title
#, no-c-format
msgid "Active/Passive Redundancy"
msgstr ""
#. Tag: para
#, no-c-format
msgid "Pacemaker also supports multiple nodes in a shared-failover design, reducing hardware costs by allowing several active/passive clusters to be combined and share a common backup node."
msgstr ""
#. Tag: title
#, no-c-format
msgid "Shared Failover"
msgstr ""
#. Tag: para
#, no-c-format
msgid "When shared storage is available, every node can potentially be used for failover. Pacemaker can even run multiple copies of services to spread out the workload."
msgstr ""
#. Tag: title
#, no-c-format
msgid "N to N Redundancy"
msgstr ""
|
