我正在创建一个通过 3 台主机的 SSH 隧道，首先到 host1，然后到跳转服务器，然后到 host2。
我像这样创建隧道：
ssh -t -A -l myusername host1.com -L 2222:localhost:2222 ssh -t -A -l myusername jumpserver.com -L 2224:localhost:2224 ssh -t -A -l muysername host3.com -L 2226:localhost:2226
隧道创建没有错误，并且打开了与 host3.com 的新连接。
因此，在另一个 bash 窗口上，我尝试通过本地主机绑定实际连接到隧道：
ssh localhost -p 2222 -vvv
这里，SSH 似乎无法在身份验证时成功使用 id_rsa 密钥，而是依靠密码请求，这总是导致权限被拒绝。
以下是调试输出：
$ ssh localhost -p 2222 -vvv
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to localhost [127.0.0.1] port 2222.
debug1: Connection established.
debug3: Incorrect RSA1 identifier
debug3: Could not load "/Users/csalvia/.ssh/id_rsa" as a RSA1 public key
debug1: identity file /Users/csalvia/.ssh/id_rsa type 1
debug1: identity file /Users/csalvia/.ssh/id_rsa-cert type -1
debug1: identity file /Users/csalvia/.ssh/id_dsa type -1
debug1: identity file /Users/csalvia/.ssh/id_dsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.0p1 Debian-4
debug1: match: OpenSSH_6.0p1 Debian-4 pat OpenSSH*
debug2: fd 5 setting O_NONBLOCK
debug3: put_host_port: [localhost]:2222
debug3: load_hostkeys: loading entries for host "[localhost]:2222" from file "/Users/csalvia/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /Users/csalvia/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],ssh-rsa
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],ssh-rsa,[email protected],[email protected],ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,[email protected],[email protected],aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,[email protected],[email protected],aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-sha1,[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-sha1,[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug2: dh_gen_key: priv key bits set: 131/256
debug2: bits set: 496/1024
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: RSA 5d:05:40:ec:2e:d9:b0:d4:ec:e4:4a:f4:97:e7:21:55
debug3: put_host_port: [127.0.0.1]:2222
debug3: put_host_port: [localhost]:2222
debug3: load_hostkeys: loading entries for host "[localhost]:2222" from file "/Users/csalvia/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /Users/csalvia/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug1: Host '[localhost]:2222' is known and matches the RSA host key.
debug1: Found key in /Users/csalvia/.ssh/known_hosts:1
debug2: bits set: 538/1024
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /Users/csalvia/.ssh/id_rsa (0x7fa164000350),
debug2: key: /Users/csalvia/.ssh/id_dsa (0x0),
debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /Users/csalvia/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Authentications that can continue: publickey,password
debug1: Trying private key: /Users/csalvia/.ssh/id_dsa
debug3: no such identity: /Users/csalvia/.ssh/id_dsa: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
csalvia@localhost's password:
debug3: packet_send2: adding 48 (len 65 padlen 15 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentications that can continue: publickey,password
Permission denied, please try again.
csalvia@localhost's password:
... 输出如下ssh-add -l：
2048 fb:37:43:08:6a:c4:c9:d3:44:2f:48:32:b7:79:35:d7 /Users/csalvia/.ssh/id_rsa (RSA)