On 14/12/2018 06:13, Viktor Dukhovni wrote:
>
>
>> On Dec 13, 2018, at 8:25 PM, Alex <mysqlstud...@gmail.com> wrote:
>>
>> We had a Mimecast user report today that their mail was being rejected
>> with a 4.7.0 "too many connections" error. This is a "soft" error, in
>> that the mail client will later attempt to resend, correct?
>
> Should be.
>
>> Isn't the default of 50 concurrent connections sufficient for most
>> environments? Is there really any reason I should consider increasing
>> that limit?
>
> Do read the log you post...
>
>> Dec 13 17:01:18 mail03 postfix/smtpd[27153]: warning: Connection
>> concurrency limit exceeded: 5 from us-smtp-delivery-100.mimecast.com[2
>> 16.205.24.100] for service smtpd
>
> 5 < 50.
I have a hunch that this is an excess count. Some while ago I had a mini-DoS
attack. As I recall, the server accepted
the first 50 connections and then started counting the refusals.
Earlier log entries should prove it one way or the other.
Allen C
