Mar 31 2012

MySQL: Resync a Master-Slave replication.

Replication enables data from one MySQL database server (the Master) to be replicated to one or more MySQL database servers (the Slaves).

Replication is asynchronous: slaves need not be connected permanently to receive updates from the master.
Depending on the configuration, it is possible to replicate all databases, selected databases, or even selected tables within a database.

This is a Step-by-Step procedure to RESYNC a Master-Slave MySQL Cluster.
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Mar 17 2012

CMAN & Two-Nodes cluster: prevent rgmanager “Quorum Dissolved”.

Ordinarily, the loss of quorum after one out of two nodes fails will prevent the remaining node from continuing (if both nodes have one vote.)

Special configuration options can be set to allow the one remaining node to continue operating if the other fails.
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Mar 5 2012

Juniper SRX: Copy a file from one node to another one in a JSRP Chassis Cluster.

When Chassis Cluster is enabled, it is possible to transfer a file from one node to the other.

An example scenario would be if it’s required to move a JunOS image from one node to the other to upgrade both nodes.
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Jan 29 2012

Upgrade JunOS on SRX Chassis Clusters.

SRX devices in a Chassis Cluster have a requirement to not have different version of JunIS on each node of the cluster.

Because of this, it is very important to ensure that both devices in the cluster come online at the same time.
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Jan 28 2012

Juniper SRX: Initiating a Chassis Cluster “Manual Redundancy Group Failover”.

It is possible to initiate a failover state manually (from the CLI) with the request command.

A manual failover bumps up the priority of the redundancy group for the specified member to 255, triggering its state.
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