如何在Server上设定，如果外部寄来的电邮超过限制的大小就拒收呢？你可以修改/etc/sendmail.cf：
Mlocal, P=/bin/mail, F=lsDFMrmn, S=10, R=20/40,
Maxsize=1000000,
A=mail -d $u
Mprog, P=/usr/local/sendmail/smrsh, F=lsDFMeu, S=10, R=20/40, D=$z:/,
Maxsize=1000000,
A=sh -c $u
This limits incoming mail processed by by smrsh and /bin/mail to 1
million bytes.
You can do the same with the Mstmp, Mesmtp, and Mrelay statements to
limit the size of outgoing mail as well.