[iJumbo]

does anyone knows if sending over 6000 emails at the same time can overload the server regardless of server configuration ?

[Kyle]

I would send them in batches, probably 100 at a time.

EDIT: If you're subscribed to something and you get an email, if you have another email registered with them you will notice it isn't at the same time. Due to they are sent out in batches.

[iLinx]

Never send out 6000 emails at a time.

[iJumbo]

so is better to cronjob a script?

[-Prodigy-]

Yes that would do just fine

[linuxthefish]

You should look into a mail sending service such as http://mailchimp.com, I've used them successfully before.

Most server hosts won't like you sending lots of email at once, as it might get their IP blacklisted!

https://www.digitalocean.com/tos

Quote:

2.4 In addition to being forbidden from performing any acts made illegal by the CAN-SPAM Act, Users may not send bulk email utilizing their Network resources unless they maintain a double-authorized list of subscribed members including IP addresses and relevant contact information, along with following guidelines for including removal links with all sent emails according to the CAN-SPAM act. Users are forbidden from taking any action that would result in their IP addresses, or any IP address associated with DigitalOcean or other Users, being placed on the Spamhaus.org blacklist.

[woot]

Alternatively, use an email delivery service. (mailchimp.com, sendgrid.net, ..)

[mamorunl]

6000 emails would take up about 4 minutes or so, depending on the server configuration and the amount of resources available.

We had a spam attack once with 30k e-mails. Server was really slow but we were seeing the e-mails get sent fairly quick - yes, before we could act and stop the server.