대량의 스팸메일이 본 도메인 smtp서버를 통해 발송되는것 같은데요?
어떻게 해야 되나요?

최근 몇일간 smtp 로그파일이 3메가~1메가 용량입니다.
안에있는 내용은 다음과 같구요


2004-07-15 00:17:59 king waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:17:59 aaas waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:17:59 king waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:17:59 babcock waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:17:59 aabb waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:00 day waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:00 eyebright waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:00 king waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:00 aaab waterfirst.snu.ac.kr ****@**** 3999 0
2004-07-15 00:18:00 bob waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:00 aback waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:01 tom waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:01 baby waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:01 aback waterfirst.snu.ac.kr ****@**** 3550 0
2004-07-15 00:18:01 eyebright waterfirst.snu.ac.kr ****@**** 3550 0