Oct 1 21:27:02 www sendmail[11584]: NOQUEUE: timeout waiting for input from 24-216-205-33.hsacorp.net during server cmd read
Oct 1 21:27:02 www sendmail[11584]: NOQUEUE: Null connection from 24-216-205-33.hsacorp.net [24.216.205.33]
Oct 1 21:27:03 www sendmail[11599]: NOQUEUE: timeout waiting for input from 24-216-205-33.hsacorp.net during server cmd read
Oct 1 21:27:03 www sendmail[11599]: NOQUEUE: Null connection from 24-216-205-33.hsacorp.net [24.216.205.33]

What does that mean?

I've recently had trouble with this user using us to spam and has been the cause of my mail server contionusly crashing.

Block the IP? Block it at the router if you have to. :)

As i dont have access to the router how do i block it?

I've got the domain he used orginally to send mail blocked through the blocking option of email parameters.

Originally posted by Technics
As i dont have access to the router how do i block it?

I've got the domain he used orginally to send mail blocked through the blocking option of email parameters.
You already pay someone who has access to that router. :) Fire off an email or give them a call. Providers are usually very willing to block abusive IPs.

Already contacted my host tera-byte just waiting for a response .. I was just wondering if there was something i could do on my machine.

What does that actually mean that i posted from my email logs?

I don't know, I don't use sendmail (long live qmail). But as for what you can do, install a firewall (if you don't already have one) and just deny the IP from your box. If you're using Linux, check the Linux Firewall HOWTOs. If you're using FreeBSD, check out an ipfw HOWTO.

Realistically, your provider should be able to help you with attacks like that, but having a firewall never ever hurts. :)