It appears that EHLO blocks do not honor allow-listed (whitelist) IPs -- is this by design?
SMTP > EHLO BLOCK(?) > WHITELIST(?) seems to be the order connections are processed on SMTP --
We have this block [*.*.*.*] which protects us from a TON of login attemps -- but we have several users with devices that don't identify with a hostname and instead use EHLO [IPv6:::ffff:###.###.###.###] -- and we were attempting to allow-list their IPs but this fails due to processing order.
SMTP EHLO blocks and allow-list
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Re: SMTP EHLO blocks and allow-list
Hi,
Sorry, it is just a straight block, without any exception possible. The whitelist of IPs only avoids RDNS, PTR check, greylisting and SPF checks.
Sorry, it is just a straight block, without any exception possible. The whitelist of IPs only avoids RDNS, PTR check, greylisting and SPF checks.