我有两台服务器。说A和B。
我ssh-copy-id在两台服务器上互相发送信息。
我可以在没有密码的情况下从 A 连接到 B。但是我无法从B连接到A。
我发现审计日志不一样
B's log when connecting from A to B (success)
... (hostname=192.168.0.1, addr=192.168.0.1, terminal=sshd ref=success
A's log when connecting from B to A (failed)
... (hostname=?, addr=192.168.0.1, terminal=sshd ref=failed
我应该去哪里调查？
这是所ssh -v显示的。
$ ssh -v user@<a's ip address>
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to <a_ip_address> [a_ip_address] port 22.
debug1: Connection established.
debug1: identity file /home/user/.ssh/identity type -1
debug1: identity file /home/user/.ssh/id_rsa type 1
debug1: identity file /home/user/.ssh/id_dsa type -1
debug1: loaded 3 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-cbc hmac-md5 none
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host '<a_ip_address>' is known and matches the RSA host key.
debug1: Found key in /home/<user>/.ssh/known_hosts:8
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Next authentication method: gssapi-with-mic
debug1: Unspecified GSS failure. Minor code may provide more information
Unknown code krb5 195
debug1: Unspecified GSS failure. Minor code may provide more information
Unknown code krb5 195
debug1: Unspecified GSS failure. Minor code may provide more information
Unknown code krb5 195
debug1: Next authentication method: publickey
debug1: Trying private key: /home/<user>/.ssh/identity
debug1: Offering public key: /home/<user>/.ssh/id_rsa
debug1: Authentications that can continue: publickey,gssapi-with-mic,password
debug1: Trying private key: /home/<user>/.ssh/id_dsa
debug1: Next authentication method: password
user@<a_ip_address>'s password:
答案1
我的问题的根本原因是.ssh目标服务器上的主目录、目录及其子文件的权限错误。
我通过查看 、和/var/log等日志文件中的消息发现了这个问题。secureaudit/*
答案2
要回答所提出的问题，即使事实证明它们不是OP的实际问题，以防搜索者正在寻找该实际问题：
UseDNS如果配置选项打开，sshd 会尝试确定客户端的主机名。上游默认值是“yes”，直到 2015 年 3 月的 6.8（就在 Q 发布之后），但发行版或软件包可能会更改默认值，当然，系统管理员始终可以覆盖默认值。但是客户端主机名的可用性和/或正确性对公钥身份验证没有影响，只会影响日志条目中的一些信息。ssh-copy-id如此命名是因为它复制一个隐式标识的公钥文件用户-- 不是主机 -- 这些文件默认的命名方式是这样的，id_rsa.pub id_dsa.pub id_ecdsa.pub id_ed25519.pub尽管可以更改。公钥文件可能（或可能不）包含给出用户名的注释，并且默认情况下ssh-keygen创建此注释作为userid@hostname键所在的位置生成的（这可能与密钥用于连接的位置不同），但这可以被覆盖、更改或删除。