sendmail 분석 좀 부탁드리겠습니다

어제밤부터 sendmail이 이렇게 주기적으로 발송이 되었습니다.
그래서 서버과부화가 걸려서 서버가 뻗어버렸네요 ㅜ
이게 무엇때문에 그런건지 이유 좀 알려주세요
그리고 막는방법도 좀 갈켜주세요
부탁드리겠습니다.
우선 sendmail 프로세스를 죽여놓은 상태입니다.

Mar 28 10:36:02 localhost sendmail[8428]: s2S1a1bk008428: from=root, size=600, class=0, nrcpts=1, msgid=<201403280136.s2S1a1bk008428@localhost.localdomain>, relay=root@localhost
Mar 28 10:36:02 localhost sendmail[8428]: s2S1a1bk008428: to=root, ctladdr=root (0/0), delay=00:00:01, xdelay=00:00:00, mailer=relay, pri=30600, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: Connection refused by [127.0.0.1]
Mar 28 10:37:01 localhost sendmail[8492]: s2S1b14Q008492: from=root, size=600, class=0, nrcpts=1, msgid=<201403280137.s2S1b14Q008492@localhost.localdomain>, relay=root@localhost
Mar 28 10:37:01 localhost sendmail[8492]: s2S1b14Q008492: to=root, ctladdr=root (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30600, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: Connection refused by [127.0.0.1]
Mar 28 10:38:02 localhost sendmail[8556]: s2S1c1lO008556: from=root, size=600, class=0, nrcpts=1, msgid=<201403280138.s2S1c1lO008556@localhost.localdomain>, relay=root@localhost
Mar 28 10:38:02 localhost sendmail[8556]: s2S1c1lO008556: to=root, ctladdr=root (0/0), delay=00:00:01, xdelay=00:00:00, mailer=relay, pri=30600, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: Connection refused by [127.0.0.1]
Mar 28 10:39:01 localhost sendmail[8681]: s2S1d1J9008681: from=root, size=600, class=0, nrcpts=1, msgid=<201403280139.s2S1d1J9008681@localhost.localdomain>, relay=root@localhost