ssh登陆提示Too many authentication failures for wyq
2014年5月05日 16:58
碰到使用ssh登陆，直接出现认证失败次数太多的问题.
在自己机器上模拟了下面测试.
ssh登陆系统，未输入密码就提示认证失败
[wyq@localhost ~]$ ssh wyq@192.168.1.107 Received disconnect from 192.168.1.107: 2: Too many authentication failures for wyq
查看/etc/sshd/sshd_config尝试认证次数
MaxAuthTries 1
最大认证次数为1，为什么还没有输入密码就已经提示 Too many authentication failures ？
开启ssh的debug模式
[wyq@localhost ~]$ ssh -v wyq@192.168.1.107 OpenSSH_6.4, OpenSSL 1.0.1e-fips 11 Feb 2013 debug1: Reading configuration data /home/wyq/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 51: Applying options for * debug1: Connecting to 192.168.1.107 [192.168.1.107] port 22. debug1: Connection established. debug1: identity file /home/wyq/.ssh/id_rsa type 1 debug1: identity file /home/wyq/.ssh/id_rsa-cert type -1 debug1: identity file /home/wyq/.ssh/id_dsa type -1 debug1: identity file /home/wyq/.ssh/id_dsa-cert type -1 debug1: identity file /home/wyq/.ssh/id_ecdsa type -1 debug1: identity file /home/wyq/.ssh/id_ecdsa-cert type -1 debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_6.4 debug1: Remote protocol version 2.0, remote software version OpenSSH_6.4 debug1: match: OpenSSH_6.4 pat OpenSSH* debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-ctr hmac-md5-etm@openssh.com none debug1: kex: client->server aes128-ctr hmac-md5-etm@openssh.com none debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug1: Server host key: ECDSA 66:29:e1:f3:32:92:64:da:98:bc:ab:f8:9c:a4:63:02 debug1: Host '192.168.1.107' is known and matches the ECDSA host key. debug1: Found key in /home/wyq/.ssh/known_hosts:21 debug1: ssh_ecdsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: Roaming not allowed by server debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug1: Next authentication method: gssapi-keyex debug1: No valid Key exchange context debug1: Next authentication method: gssapi-with-mic debug1: Unspecified GSS failure. Minor code may provide more information Cannot determine realm for numeric host address debug1: Unspecified GSS failure. Minor code may provide more information Cannot determine realm for numeric host address debug1: Unspecified GSS failure. Minor code may provide more information debug1: Unspecified GSS failure. Minor code may provide more information Cannot determine realm for numeric host address debug1: Next authentication method: publickey debug1: Offering RSA public key: /home/wyq/.ssh/id_rsa debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug1: Trying private key: /home/wyq/.ssh/id_dsa debug1: Trying private key: /home/wyq/.ssh/id_ecdsa debug1: Next authentication method: password wyq@192.168.1.107's password:
发现在提示输入密码前它已经进行了几次验证
debug1: Next authentication method: gssapi-keyex debug1: Next authentication method: gssapi-with-mic debug1: Next authentication method: publickey debug1: Next authentication method: password
原来在密码认证之前，ssh已经进行了几种认证.
应该是他们导致的，具体原因就不是很清楚.
还有一个问题就是MaxAuthTries值再大，也只能输入三次密码.
这个问题也很疑惑的.
挺奇怪的，管理人员怎么喜欢修改MaxAuthTries的值？
ssh登陆密码输入错误，被中断后，别人再ssh不行吗？
默认值很合理的，完全没有必要修改.
