Preparing for Maintenance Version Upgrades for 4.2
Before attempting to perform a rolling upgrade for 4.2, confirm the following:
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Ensure that all of the Terracotta servers and clients in the target cluster are running the same version of Terracotta.
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Ensure that the upgrade is intended for the version of Terracotta being run in your cluster.
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If persistence is enabled in your cluster, we recommend that you back up your data folder before upgrading, as described in "Database Backup Utility (backup-data) in the
BigMemory Max Administrator Guide.
Note: A non-persistent cluster without mirror servers cannot be upgraded without losing all the data.