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- Ensure that the X-Road software on all nodes is at version 6.20.0/1 or 6.21.0 (N.B.! all nodes must have the same version), and all Ubuntu packages are updated.
- If necessary, update the cluster, following instructions in [1], section 7.
- Pause the database and configuration synchronization on the slave nodes ([1], section 7.2.1)
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