I was wondering if my FTP server to FTP attack?-CodePudding

The following is FTP logging:
Recently have not used the FTP according to a week or two, all FTP log is generated every day in records, and FTP anonymous logins are closed, if is to attack, what method can solve?

# Software: Microsoft Internet Information Services 7.0
# Version: 1.0
# Date: 2017-01-11 02:51:40
IP # Fields: time c - cs - method cs - uri - stem sc - the status of sc - win32 - status
02:51:40 122.224.153.109 [39208] closed - 421-121
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS - 530-1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] 530, 1326 PASS the admin
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS, 123456, 530, 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS FTP 530 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS test 530 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
Qazxsw2 08:10:15 140.205.225.183 [39471] PASS 1 530 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS, 123, 530, 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] PASS, 12345678, 530, 1326
08:10:15 140.205.225.183 [39471] USER anonymous 331 0
08:10:15 140.205.225.183 [39471] 530 1326 PASS the root
08:10:15 140.205.225.183 [39471] USER FTP 331 0
08:10:15 140.205.225.183 [39471] PASS - 530-1326
08:10:15 140.205.225.183 [39471] USER FTP 331 0
08:10:15 140.205.225.183 [39471] 530, 1326 PASS the admin
08:10:15 140.205.225.183 [39471] USER FTP 331 0
08:10:15 140.205.225.183 [39471] PASS, 123456, 530, 1326
08:10:15 140.205.225.183 [39471] USER FTP 331 0
08:10:15 140.205.225.183 [39471] PASS FTP 530 1326
08:10:15 140.205.225.183 [39471] USER FTP 331 0
08:10:16 140.205.225.183 [39471] PASS test 530 1326
08:10:16 140.205.225.183 [39471] USER FTP 331 0
Qazxsw2 08:10:16 140.205.225.183 [39471] PASS 1 530 1326
08:10:16 140.205.225.183 [39471] USER FTP 331 0
08:10:16 140.205.225.183 [39471] PASS, 123, 530, 1326
08:10:16 140.205.225.183 [39471] USER FTP 331 0
08:10:16 140.205.225.183 [39471] PASS, 12345678, 530, 1326
08:10:16 140.205.225.183 [39471] USER FTP 331 0
08:10:16 140.205.225.183 [39471] 530 1326 PASS the root
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:16 140.205.225.183 [39471] the USER test 331 0
08:10:16 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] the USER test 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER admin 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER USER 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER USER 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:17 140.205.225.183 [39471] USER USER 331 0
08:10:17 140.205.225.183 [39471] PASS - 530-1326
08:10:18 140.205.225.183 [39471] USER USER 331 0
08:10:18 140.205.225.183 [39471] PASS - 530-1326
08:10:18 140.205.225.183 [39471] USER USER 331 0
08:10:18 140.205.225.183 [39471] PASS - 530-1326
08:10:18 140.205.225.183 [39471] USER USER 331 0
08:10:18 140.205.225.183 [39471] PASS - 530-1326
08:10:18 140.205.225.183 [39471] USER USER 331 0
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