[Dovecot] pop3 rate limit

Hi,

we have customers with Exchange servers that are polling for new mail every minute with dozens of pop3 accounts. I am looking for a mechanism to rate limit this per user. So what I am looking for is a way to block users from polling, if a user asks for new mail more than every 5 minutes (for example).

Is this possible? Can this be achieved within Dovecot or does it need external scripting? (I thought about fail2ban, but also want IPv6 support)

Thanks in advance

-Christian Rößner

-- [*] sys4 AG

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