Upgrading to Aerospike Server version 4.5.1 or newer - Backup the Aerospike System MetaData (SMD) file
In the unlikely event of having to perform a downgrade from Aerospike Server version 4.5.1 or newer to Aerospike Server version 188.8.131.52 or earlier (or version 184.108.40.206), the System Meta Data (SMD) content needs to be manually restored from the earlier running version. Downgrading in place will cause all SMD content to be lost. This includes: Secondary index, UDF, security, truncate and eviction entries. Therefore, prior to upgrading to Aerospike Server version 4.5.1 or above, from an earlier version, backup the System MetaData (SMD) files. The default location for the System MetaData files is /opt/aerospike/smd. If no backup exists the SMD definitions will need to be rebuilt when downgrading.
Make a backup of the System MetaData file (/opt/aerospike/smd) ?
The System MetaData (SMD) files by default are installed in /opt/aerospike/smd
Always review the Aerospike Server release notes between versions to familiarize yourself with any specific downgrade/rollback steps. Also review the Special Upgrades page for any special instructions for upgrading/downgrading.
rollback update install downgrade smd system metadata
May 24 2019