This section provides information on performing a major upgrade of the VMs from RVT 4.0.
Each of the links below contains standalone instructions for upgrading a particular node type, in addition to one page of steps to perform prior to upgrading any node type. The normal procedure is to upgrade only one node type in any given maintenance window, though you can upgrade multiple node types if the maintenance window is long enough.
Most call traffic will function as normal when the nodes are running different versions of the software. However, do not leave a deployment in this state for an extended period of time:
Certain call types cannot function when the cluster is running mixed software versions. These call types include reorigination and SRVCC.
Part of the upgrade procedure is to disable scheduled tasks for the duration of the upgrade. Without these tasks running, the performance and health of the system will degrade.
Upgrade the nodes in the exact order described below. Always finish upgrading all nodes of one node type before starting on another node type.