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Command has to be executed on the Master node and requires root permissions. Following may be used:

...

The tool requires root permissions. The list of arguments and other requirements depend on the command used. Please refer to below table for a summary and respective sections for details.

status

init-master

init-slave

promote

sync-files

remove-node

Init Master

Cluster Status

The command shows Cluster Status, including all nodes with their roles, IP addresses, current lag to Master and overall status.

<APP_PATH>/bin/system/cluster status

The command can be executed on the Master in order to get the most detailed information about the cluster:

Image Added

Alternatively command can be executed at any other node - in this case only status of the connection between this particular node and the Master will be shown.

If any node failed and has been disconnected from the cluster it will be shown like this:

Image Added

In this case you have to re-check failed node, fix it and then return to the cluster using "init-slave" command.

Init Master

The command is used for initial configuration of the Master NodeThe command is run on Master and used for Master to configure its parameters.

<VCS<APP_PATH>/bin/system/cluster init-master --ip=<IP-of-master>ADDRESS> [<extra-options>]<options>]

Command has to be executed on the Master node and requires root permissions. Following options are supportedThis command may require additional options:

<IP-

ADDRESS>

none

--ssh-port=<port>

22

--pg-data=<path>

autodetect

--vcs-path=<path>

<VCS_PATH>

...

Init Slave

The command is run on the Master and used for:is used to add node to the cluster. There are different contexts when it is required:

• First-time deployment of the cluster
• Addition on a new slave node to the cluster
• Addition of the
• first-time initialization of the cluster;
• addition of the new slave node to the cluster;
• addition of the  old master to work as a slave  after failover.after fail over

<VCS<APP_PATH>/bin/system/cluster init-slave --ip=<IP-of-slave>ADDRESS> [<extra-options>]

This command encapsulates 4 sub-commands:

• configuration of the Master to ship replication logs (init-master)
• configuration of the Master to accept connections from the Slave (init-master-access)
• configuration of the Slave to receive replication logs (init-slave)
• show status of the cluster (status).

Each of these commands may be performed separately if you know exactly what you need.

This command may require additional options:

<options>]

Command has to be executed on the Master node and requires root permissions. Following options are supported:

--ip=<ip>

none

<IP-ADDRESS>

--role=<role>

redundancy

--ssh-port=<port>

22

--ssh-

user=

<user>

jerasupport

--pg-data=<path>

--vcs-path=<path>

<VCS_PATH>

--role=<role>

redundancy

...

autodetect

Promote  to Master

The command is run on the Slave and used to promote the current Slave Redundancy node to Master. 

<VCS<APP_PATH>/bin/system/cluster promote

Command has to be executed on the Redundancy node and requires root permissions. Reporting node can be used as a last resort if there are no Redundancy node alive. There are no options required.

After promotion is performed, all required System Services will be started on the current node (new master)The command is used for failover. After you fix old Master, you may add it as a new Slave using "init-slave" command.

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Sync Files

The command is run on the Slave and used to synchronize files sync data and application files from the Master. The command is mostly used in crontab for auto-sync.

<VCS<APP_PATH>/bin/system/cluster sync-files

During initialization of the cluster, tool adds this command to the crontab (/etc/cron.d/vcs-cluster) at the Slave node. 

Cluster Status

Command has to be executed on the Redundancy node and by default it is added to the crontab for automatic synchronisation.

Remove Node

The command may be run on any node and used to get status of the cluster. The command is used to remove node from the cluster.

<VCS<APP_PATH>/bin/system/cluster status

When the command is run on the Master, it shows the type of the node and attached Slaves that are up to date:

[ NOTICE ] Cluster Status
  ifconfig  | grep 'inet addr:'| grep -v '127.0.0.1' | cut -d: -f2 | awk '{ print $1}'

Master (master ip): ACTIVE 
    Redundancy (slave ip): ACTIVE

When the command is run on the Slave, it shows the type of the node and synchronization delay.

[ NOTICE ] Cluster Status
  ifconfig  | grep 'inet addr:'| grep -v '127.0.0.1' | cut -d: -f2 | awk '{ print $1}'

Master (master ip): NOT AVAILABLE | Activity delay: -00:00:58.393423
    Redundancy (slave ip): ACTIVE

Please don't worry if you see the following:

the row: Master (master ip): NOT AVAILABLE 

It's normal behavior. Instead, please pay attention to Activity delay parameter − it shows large values if replication is broken and servers are not in sync. 

...

remove-node <IP-ADDRESS>

Command has to be executed on the Master node. The node in question shouldn't have any active database replication. Following options are supported:

<IP-ADDRESS>