On Fri, Sep 02, 2016 at 05:33:33PM +0200, Tom wrote:
On Fri, Sep 02, 2016 at 08:08:39AM -0700, Razer wrote:
I just took a look at the Wikipedia entry for 'greylisting'. It sounds awful if you're victimized by it. My personal mail from openmailbox to a friend was rejected by yahoo b/c of shit like that and I didn't get a notifcation for three fucking days.
Obviously you've never operated an email server. 99% of all emails arriving on any bigger public mail server is spam. Of course you do everything to minimize spam.
Since most spam comes from bot nets which do not implement queueing as required by the RFCs, they are successfully blocked from delivering their spam with greylisting.
Of course this method blocks mails coming from mailservers whose operators are stupid morons and do not properly configure queueing.
I don't remember operating public SMTPD. The issue with spam is just temporary kludge. Queue support via "try again later" is very easy to implement in a bot -- just precompiled qmail or some lightweight SMTPD would do AFAICT. It is just a matter of time till spammers do it. Also, nearly all ISPs have non-negligible amount of users with malware and some of it may send spam via the ISP's SMTPD. It is mystery to me why aren't all ISPs blacklisted. Heard that some Spam Black List operators are fucked up morons, don't know how true is this. As an aside, I know admin who blocked access of all Chinese IPs to SMTP to fight spam (maybe he blocked them totally, not sure).