limiting POP3/IMAP access frequency
 

Hi,

My server listens to POP3/IMAP requests. Some users have configured their mailers with high checking frequencies, say once every minute, such that the system logs are full of entries with no significance at all.

I'd like to ask if there is a way to limit the per IP frequency of POP3/IMAP access ?

I'm using "xinetd" to wrap the "ipop3d" and "imapd" which come with the Alpine package.


Best regards,
anctop

See "per_source" in 'man xinetd.conf' or iptables "limit" module 'iptables --help -m limit'?

Thanks for the information, but they do not help for my case.

The "per_source" of xinetd, or the "connlimit" of iptables, only limits the number of concurrent connections. This has already been implemented, but I'm looking for a way to limit the hit frequency of each client.

The "limit" of iptables seems to limit the overall rate, not counting per IP. My system serves quite many users. Most of the clients are properly configured except for a few ones, therefore I don't want to implement a global rate limit which may also affect those well-behaved users.

I meant to write "recent", not "limit".

I think this is what I'm looking for.
Thank you very much.