Tag Archives: Pacemaker

RHEL 7 – How to configure the Fencing on Pacemaker ?


Fencing (STONITH) is an important mechanism in cluster to avoid the data corruption on shared storage. It also helps to bring the cluster into the known state when there is a split brain occurs between the nodes. Cluster nodes talks to each other over communication channels, which are typically standard network connections, such as Ethernet. Each resources and nodes have “state” …

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RHEL 7 – Pacemaker – Configure Redundant Corosync Links on Fly– Part 10

Corosync Links - RHEL7

Corosync cluster engine provides the reliable inter-cluster communications between the cluster nodes. It syncs the cluster configuration across the cluster nodes all the time. It also maintains the cluster membership and notifies when quorum is achieved or lost. It provides the messaging layer inside the cluster to manage the system and resource availability. In Veritas cluster , this functionality has been provided by LLT + …

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RHEL 7 – Pacemaker – Define the Resource Behaviour – Part 9

Pacemaker resource agents

In Pacemaker/Corosync cluster, there are may aspects/key elements that we need to understand before playing with cluster operations. Otherwise , it might cause unnecessary outage/downtime for the services. The most important elements are setting the preferred resource location , ordering (defining dependencies) , resource fail counts, resource-stickiness, colocation, clone, master/slave, promote/demote etc. Let’s go through the article and understand how these elements contributes …

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RHEL 7 – Redhat Cluster with Pacemaker – Overview – Part 2

Redhat Cluster with Pacemaker

Pacemaker is robust and powerful opensource resource manager  which is shipping with  Redhat Enterprise Linux 7 as High Availability Add-on . Pacemaker simplified the cluster configuration and cluster management on RHEL 7 which is really good for system administrators. Compare to the prior redhat cluster release, Redhat cluster 7 looks completely different with corosync cluster engine and pacemaker resource manager. In this …

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Compare Redhat Cluster Releases – RHEL 7 HA vs RHEL 6 HA – Part 1

Redhat Cluster 7 vs Redhat cluster 6

In this article ,we will see the difference between Redhat cluster 6.x (Red Hat Enterprise Linux High Availability Add-On Release 6) and Redhat Cluster 7.x releases (Red Hat Enterprise Linux High Availability Add-On Release 7). In RHEL7 onwards “pacemaker” is the default cluster resource manager.  Corosync is open source cluster engine which is responsible to manage the cluster interconnect and …

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