我正在使用CentOS v7，我试图设置MaxAuthTries 6虽然这似乎不工作。 我正在使用PAM，所以属性UsePAM yes被设置。 我不知道是否是一个错误或其他东西阻止authentication尝试超过3。
在日志中，我得到了下面的结果
[root@webserver ~]# sshd -T | grep -i 'pam\|authtries\|gracetime' usepam yes logingracetime 600 maxauthtries 6 [root@webserver ~]# tail -f /var/log/secure Mar 26 12:04:41 webserver systemd: Stopping OpenSSH server daemon... Mar 26 12:04:41 webserver systemd: Starting OpenSSH server daemon... Mar 26 12:04:41 webserver systemd: PID file /var/run/sshd.pid not readable (yet?) after start. Mar 26 12:04:41 webserver sshd[2308]: Server listening on 0.0.0.0 port 22. Mar 26 12:04:41 webserver sshd[2308]: Server listening on 0.0.0.0 port 22. Mar 26 12:04:41 webserver sshd[2308]: Server listening on :: port 22. Mar 26 12:04:41 webserver sshd[2308]: Server listening on :: port 22. Mar 26 12:04:41 webserver polkitd[687]: Unregistered Authentication Agent for unix-process:2301:105272 (system bus name :1.23, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8) (disconnected from bus) Mar 26 12:04:41 webserver polkitd[687]: Unregistered Authentication Agent for unix-process:2301:105272 (system bus name :1.23, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8) (disconnected from bus) Mar 26 12:04:41 webserver systemd: Started OpenSSH server daemon. Mar 26 12:05:16 webserver unix_chkpwd[2318]: password check failed for user (test) Mar 26 12:05:16 webserver unix_chkpwd[2318]: password check failed for user (test) Mar 26 12:05:16 webserver sshd[2316]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=gateway user=test Mar 26 12:05:16 webserver sshd[2316]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=gateway user=test Mar 26 12:05:18 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:18 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:20 webserver unix_chkpwd[2319]: password check failed for user (test) Mar 26 12:05:20 webserver unix_chkpwd[2319]: password check failed for user (test) Mar 26 12:05:22 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:22 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:25 webserver unix_chkpwd[2320]: password check failed for user (test) Mar 26 12:05:25 webserver unix_chkpwd[2320]: password check failed for user (test) Mar 26 12:05:27 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:27 webserver sshd[2316]: Failed password for test from 192.168.124.1 port 48936 ssh2 Mar 26 12:05:27 webserver sshd[2316]: Connection closed by 192.168.124.1 [preauth] Mar 26 12:05:27 webserver sshd[2316]: Connection closed by 192.168.124.1 [preauth] Mar 26 12:05:27 webserver sshd[2316]: PAM 2 more authentication failures; logname= uid=0 euid=0 tty=ssh ruser= rhost=gateway user=test Mar 26 12:05:27 webserver sshd[2316]: PAM 2 more authentication failures; logname= uid=0 euid=0 tty=ssh ruser= rhost=gateway user=test
客户端（ ssh_config ）有一个选项， NumberOfPasswordPrompts默认设置为3.这就是为什么我不能超越3次尝试。
NumberOfPasswordPrompts Specifies the number of password prompts before giving up. The argument to this keyword must be an integer. The default is 3.