Updating the prerequisites for upgrading to a fix pack
The second phase for upgrading to a fix pack is to update the prerequisites. The prerequisites include Cassandra and ZooKeeper.
In this phase, each Cassandra and ZooKeeper server are updated one by one, and one instance is stopped at a time. This is considered a rolling upgrade. If Cassandra and ZooKeeper are installed together, you can update them together on that server.
During the upgrade, there will be different versions of Casssandra and ZooKeeper servers in your environment. The Cassandra and ZooKeeper software is designed to mix different versions in the same cluster. All Global Mailbox operations will be successful.
On each server in each data center that contains the prerequisites, complete the following steps one server at a time:
Verify that the Global Mailbox Admin UI works by logging in and viewing some mailboxes. If
everything works fine, proceed to Updating Sterling B2B Integrator and Global Mailbox to a fix pack.