User hardening security procedures.
ClickHouse is known for its ability to scale with clusters, handle terabytes to petabytes of data, and return query results fast. It also has a plethora of built in security options and features that help keep that data safe from unauthorized users.
Hardening your individual ClickHouse system will depend on the situation, but the following processes are generally applicable in any environment. Each of these can be handled separately, and do not require being performed in any particular order.
Secure network communications with ClickHouse
Secure data stored for ClickHouse