禁止特定IP的ssh访问

solarisplayer

今天发现有主机网络中断，检查、主机、应用、网络均正常，
syslog有如下信息：
Jan  4 20:24:45 hqwls03 sshd[6187]: Did not receive identification string from 10.87.21.104
Jan  4 20:29:46 hqwls03 sshd[6360]: Did not receive identification string from 10.87.21.104
Jan  4 20:34:45 hqwls03 sshd[6522]: Did not receive identification string from 10.87.21.104
Jan  4 20:39:45 hqwls03 sshd[6684]: Did not receive identification string from 10.87.21.104
Jan  4 20:44:45 hqwls03 sshd[6859]: Did not receive identification string from 10.87.21.104
Jan  4 20:49:45 hqwls03 sshd[7023]: Did not receive identification string from 10.87.21.104
Jan  4 20:54:45 hqwls03 sshd[7189]: Did not receive identification string from 10.87.21.104
Jan  4 20:59:45 hqwls03 sshd[7362]: Did not receive identification string from 10.87.21.104
我应该怎么禁用这个IP SSH呢

lbseraph

想到下面两个方法：

1. 在文件/etc/hosts.deny里面加一行保存即可；

sshd:10.87.21.104:deny

2. 或者用IPF（防火墙）禁止该IP的ssh访问即可。