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KIP-226 added support for dynamic update of  broker configuration.  In this KIP, we propose to extend the support to dynamic update of max.connections.per.ip/max.connections.per.ip.overrides configs. This will be useful  in the situations where a particular host (or set of hosts) is causing some trouble for the brokers.  Administrators can dynamically update these configs to restrict the connections coming from faulty hosts (or)  enable connections only from certain allowed hosts.

Proposed Changes

Use case: To restrict the connections coming from faulty clients/hosts  (or) to configure IP-based filtering of incoming connections (max.connections.per.ip  = 0 and valid max.connections.per.ip.overrides config value)

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