Denial of service

[williammr]

Hi,

I have a Zimbra Mail Server updated to 5.0.10. Since 2 weeks ago my mail server is receiving a lot of connections, this is my /var/log/maillog

Oct 2 13:55:35 correo postfix/smtpd[6400]: disconnect from bay0-omc1-s26.bay0.hotmail.com[65.54.246.98]
Oct 2 13:55:38 correo postfix/smtpd[19406]: connect from blu0-omc4-s16.blu0.hotmail.com[65.55.111.155]
Oct 2 13:56:20 correo postfix/smtpd[6415]: timeout after CONNECT from blu0-omc4-s34.blu0.hotmail.com[65.55.111.173]
Oct 2 13:56:20 correo postfix/smtpd[6415]: disconnect from blu0-omc4-s34.blu0.hotmail.com[65.55.111.173]
Oct 2 13:56:24 correo postfix/smtpd[27792]: connect from blu0-omc2-s8.blu0.hotmail.com[65.55.111.83]
Oct 2 13:57:06 correo postfix/smtpd[5995]: timeout after CONNECT from blu0-omc4-s38.blu0.hotmail.com[65.55.111.177]
Oct 2 13:57:06 correo postfix/smtpd[5995]: disconnect from blu0-omc4-s38.blu0.hotmail.com[65.55.111.177]
Oct 2 13:57:07 correo postfix/smtpd[31106]: timeout after CONNECT from bay0-omc2-s38.bay0.hotmail.com[65.54.246.174]
Oct 2 13:57:07 correo postfix/smtpd[31106]: disconnect from bay0-omc2-s38.bay0.hotmail.com[65.54.246.174]
Oct 2 13:57:21 correo postfix/smtpd[12194]: timeout after CONNECT from bay0-omc2-s21.bay0.hotmail.com[65.54.246.157]
Oct 2 13:57:21 correo postfix/smtpd[12194]: disconnect from bay0-omc2-s21.bay0.hotmail.com[65.54.246.157]
Oct 2 13:57:29 correo postfix/smtpd[6400]: connect from bay0-omc1-s24.bay0.hotmail.com[65.54.246.96]

When someone send us an email to my server, this mail is taking 3 hours to arrive, when i block all the 65.0.0.0/24 on my firewall, the mail server start to manage all the mails, but obviously hotmail.com is blocked.

Is possible to block this with zimbra, what can i do?

Maybe someone deal with this before?

Thank you.

[Baylink]

Contact postmaster@hotmail.com?