Networking
連接到 IP 地址時 ssh 掛起，使用主機名時正常
使用 Mac OSX 10.6.4。我正在嘗試通過 ssh 連接到我正在使用的同一台電腦。我的電腦名稱只是 MacBookPro。簡短的版本是，當我使用它的 IP 地址 SSH 到我的機器時，它會暫停大約 40 秒，然後讓我進入。
我使用以下方法創建了一個 ssh 密鑰：
ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys通過 ssh localhost 或 ssh MacBookPro.local 進入我的機器就可以了。當我嘗試使用 ip 地址 ssh 到我的機器時，我會收到暫停。
MacBookPro:~ nkodner$ ssh -v -v -v 192.168.1.118 OpenSSH_5.2p1, OpenSSL 0.9.8l 5 Nov 2009 debug1: Reading configuration data /etc/ssh_config debug2: ssh_connect: needpriv 0 debug1: Connecting to 192.168.1.118 [192.168.1.118] port 22. debug1: Connection established. debug1: identity file /Users/nkodner/.ssh/identity type -1 debug1: identity file /Users/nkodner/.ssh/id_rsa type -1 debug1: identity file /Users/nkodner/.ssh/id_dsa type 2 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.2 debug1: match: OpenSSH_5.2 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.2 debug2: fd 3 setting O_NONBLOCK 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: ssh-rsa,ssh-dss 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,rijndael-cbc@lysator.liu.se 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,rijndael-cbc@lysator.liu.se debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib debug2: kex_parse_kexinit: none,zlib@openssh.com,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: 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 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,rijndael-cbc@lysator.liu.se 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,rijndael-cbc@lysator.liu.se debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,zlib@openssh.com debug2: kex_parse_kexinit: none,zlib@openssh.com 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: 125/256 debug2: bits set: 534/1024 debug1: SSH2_MSG_KEX_DH_GEX_INIT sent debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY debug3: check_host_in_hostfile: filename /Users/nkodner/.ssh/known_hosts debug3: check_host_in_hostfile: match line 3 debug1: Host '192.168.1.118' is known and matches the RSA host key. debug1: Found key in /Users/nkodner/.ssh/known_hosts:3 debug2: bits set: 523/1024 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: SSH2_MSG_SERVICE_REQUEST sent debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug2: key: /Users/nkodner/.ssh/id_rsa (0x100126150) debug2: key: /Users/nkodner/.ssh/identity (0x0) debug2: key: /Users/nkodner/.ssh/id_rsa (0x0) debug2: key: /Users/nkodner/.ssh/id_dsa (0x1001253c0) *<pauses for about 20 seconds here>* debug1: Authentications that can continue: publickey,keyboard-interactive debug3: start over, passed a different list publickey,keyboard-interactive 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 public key: /Users/nkodner/.ssh/id_rsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug1: Trying private key: /Users/nkodner/.ssh/identity debug3: no such identity: /Users/nkodner/.ssh/identity debug1: Trying private key: /Users/nkodner/.ssh/id_rsa debug3: no such identity: /Users/nkodner/.ssh/id_rsa debug1: Offering public key: /Users/nkodner/.ssh/id_dsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug2: we did not send a packet, disable method debug3: authmethod_lookup keyboard-interactive debug3: remaining preferred: password debug3: authmethod_is_enabled keyboard-interactive debug1: Next authentication method: keyboard-interactive debug2: userauth_kbdint debug2: we sent a keyboard-interactive packet, wait for reply debug2: input_userauth_info_req debug2: input_userauth_info_req: num_prompts 1 Password: And here's output from ssh localhost: MacBookPro:~ nkodner$ ssh -v -v -v localhost OpenSSH_5.2p1, OpenSSL 0.9.8l 5 Nov 2009 debug1: Reading configuration data /etc/ssh_config debug2: ssh_connect: needpriv 0 debug1: Connecting to localhost [::1] port 22. debug1: Connection established. debug1: identity file /Users/nkodner/.ssh/identity type -1 debug1: identity file /Users/nkodner/.ssh/id_rsa type -1 debug1: identity file /Users/nkodner/.ssh/id_dsa type 2 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.2 debug1: match: OpenSSH_5.2 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.2 debug2: fd 3 setting O_NONBLOCK 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: ssh-rsa,ssh-dss 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,rijndael-cbc@lysator.liu.se 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,rijndael-cbc@lysator.liu.se debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib debug2: kex_parse_kexinit: none,zlib@openssh.com,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: 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 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,rijndael-cbc@lysator.liu.se 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,rijndael-cbc@lysator.liu.se debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,zlib@openssh.com debug2: kex_parse_kexinit: none,zlib@openssh.com 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: 119/256 debug2: bits set: 510/1024 debug1: SSH2_MSG_KEX_DH_GEX_INIT sent debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY debug3: check_host_in_hostfile: filename /Users/nkodner/.ssh/known_hosts debug3: check_host_in_hostfile: match line 1 debug1: Host 'localhost' is known and matches the RSA host key. debug1: Found key in /Users/nkodner/.ssh/known_hosts:1 debug2: bits set: 532/1024 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: SSH2_MSG_SERVICE_REQUEST sent debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug2: key: /Users/nkodner/.ssh/id_rsa (0x100126020) debug2: key: /Users/nkodner/.ssh/identity (0x0) debug2: key: /Users/nkodner/.ssh/id_rsa (0x0) debug2: key: /Users/nkodner/.ssh/id_dsa (0x100118fa0) debug1: Authentications that can continue: publickey,keyboard-interactive debug3: start over, passed a different list publickey,keyboard-interactive 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 public key: /Users/nkodner/.ssh/id_rsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug1: Trying private key: /Users/nkodner/.ssh/identity debug3: no such identity: /Users/nkodner/.ssh/identity debug1: Trying private key: /Users/nkodner/.ssh/id_rsa debug3: no such identity: /Users/nkodner/.ssh/id_rsa debug1: Offering public key: /Users/nkodner/.ssh/id_dsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug2: we did not send a packet, disable method debug3: authmethod_lookup keyboard-interactive debug3: remaining preferred: password debug3: authmethod_is_enabled keyboard-interactive debug1: Next authentication method: keyboard-interactive debug2: userauth_kbdint debug2: we sent a keyboard-interactive packet, wait for reply debug2: input_userauth_info_req debug2: input_userauth_info_req: num_prompts 1
在我的 /etc/sshd 中，我添加了
UseDNS no這停止了反向 DNS 查找並緩解了問題。我不完全確定這是處理問題的正確方法，但它確實完成了工作。
192.168.1.118 在 /etc/hosts 中有有效的條目嗎
sshd 正在執行反向 dns 查找，並且 192.168.1.118 的兩個名稱伺服器正在超時，此時 sshd 允許連接。