Synnefo » snf-ganeti

Replication network changes

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The :command:`gnt-node modify -s` command can be used to change the

secondary IP of a node. This operation can only be performed if:

- No instance is active on the target node

- The new target IP is reachable from the master's secondary IP

Also this operation will not allow to change a node from single-homed

(same primary and secondary ip) to multi-homed (separate replication

network) or vice versa, unless:

- The target node is the master node and `--force` is passed.

- The target cluster is single-homed and the new primary ip is a change

  to single homed for a particular node.

- The target cluster is multi-homed and the new primary ip is a change

  to multi homed for a particular node.

For example to do a single-homed to multi-homed conversion::

  $ gnt-node modify --force -s %SECONDARY_IP% %MASTER_NAME%

  $ gnt-node modify -s %SECONDARY_IP% %NODE1_NAME%

  $ gnt-node modify -s %SECONDARY_IP% %NODE2_NAME%

  $ gnt-node modify -s %SECONDARY_IP% %NODE3_NAME%

  ...

The same commands can be used for multi-homed to single-homed except the

secondary IPs should be the same as the primaries for each node, for

that case.