Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

This question already has an answer here:

is there a way to limit amount of email per X amount of time to certain domains? for example I have large list of emails and I have thousands of emails for, but if I start sending them all at once yahoo will temporarily defer me thinking that I'm doing something that I'm not suppose to do, yet if I send out only 100 emails an hour they are ok with this volume, so how can I restrict sendmail to send only 100 emails an hour to

share|improve this question

marked as duplicate by Katherine Villyard, masegaloeh, Jenny D, Hyppy, mdpc Apr 22 '15 at 6:08

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

i can't believe no one ever done something like that ;( – alexus Oct 9 '09 at 14:15

There are two options:

1) If this is an actual server in your environment for users, and you're doing this from an application or a script, you should change your application or script to manage the number of emails you send over an allotted time. Otherwise, you'll cause adverse issues for your normal users.

2) You can run sendmail with -q[time] where [time] is the interval you want your mail to be sent.

Example from manpage:

`-q1h30m' or `-q90m' would both set the timeout to one hour thirty minutes.

For more information about how to use sendmail, you can read the manual here:

share|improve this answer

Yahoo actually limits number of mails per envelope generally above that of mails per hour. If you reduce the number of Yahoo addresses per individual mail, they will allow a lot more through per hour.

share|improve this answer
I'm using yahoo as an example, I don't know what they rules are, most big ESPs have some sort of rule sets, so based on some tests I can adjust it and send emails quicker rather getting deferred all the time. – alexus Sep 30 '09 at 19:41
Its the same with hotmail, live, gmail etc. Once you limit the number per envelope, you can actually send quite a few more through per hour than simply leaving a mass email. Most mailing software actually has functions to take care of this already. – Ryaner Sep 30 '09 at 21:12

Not the answer you're looking for? Browse other questions tagged or ask your own question.