Re: Delay before initial 220 greeting
- On 3/1/2012 11:42 AM, Brian Evans - Postfix List wrote:
> On 3/1/2012 11:49 AM, Alex wrote:I just fired an email to another list where a few Constant Contact folks
>>>> I had thought it was related, but another issue I'm trying to figure
>>>> out is how to prevent a single remote server from sending thousands of
>>>> messages at a time, filling the queue, and causing significant
>>>> delivery delays for all mail.
>>> Is it safe to assume these thousands of messages are spam, and not legit
>>> mail? If so, simply block the IP address(es) in a cidr table:
>>> check_client_access cidr:/etc/postfix/blacklist.cidr
>>> #single IP
>>> 10.10.10.10/32 REJECT high rate spammer
>>> #class C network
>>> 10.10.10.0/24 REJECT snowshoe spammer
>>> If it's legit mail, anvil typically takes care of rate throttling, IIRC.
>>> Need more info. What version of Postfix are you using again?
>> Yes, it is for legit mail, such as that from constantcontact and other
>> bulk mailers that overwhelm my servers and upset my users who want
>> their more important mail.
> Perhaps you would like to rate limit certain IPs?
> If so, you could apply the above map and, instead of rejecting, perform
> a check_policy_service action along with something like Postfwd.
> A policy server could also be global depending on your needs.
have been known to participate. A member (non CC) already responded
with their outbound range. Active hosts list within the range after my sig.
I also offered to put CC in contact with Alex if this rate issue might
be better addressed on their end.