私はbashを使って一連のsshコマンドを自動化し、スクリプトがコマンドラインから呼び出されたときに動作するようにします。以下は、スクリプトからのSSH呼び出しの例です。
ssh-keyscan -H $CURRENT_IP >> ~/.ssh/known_hosts
sshpass -f pass.txt ssh -o ConnectionAttempts=3 -o ConnectTimeout=10 $login exit
しかし、1日に1回スクリプトを実行するためにcronjobを追加し、sshコマンドが正しく実行されないという問題が発生しました。この問題を読んでおり、crontabはキーやその他のエントリを取得できないため、sshとcrontabの既知の問題です。私は他の質問のアドバイスに従い、最終的にsshの電話を受けました。
ssh-keyscan -H $CURRENT_IP >> ~/.ssh/known_hosts
sshpass -f pass.txt ssh -i ~/.ssh/known_hosts -o ConnectionAttempts=3 -o ConnectTimeout=10 $login exit
-iフラグを使用すると問題が解決すると思われましたが、次のエラーが発生し始めました。
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@ WARNING: UNPROTECTED PRIVATE KEY FILE! @
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Permissions 0644 for '/root/.ssh/known_hosts' are too open.
It is required that your private key files are NOT accessible by others.
This private key will be ignored.
問題を解決するためにこれを試しましたが、chmod 400 /root/.ssh/known_hostsエラーが削除されました。しかし、これにより、接続タイムアウトと試行制限にもかかわらず、SSH接続が無期限に中断されるという問題が発生しました。
キーファイルの権限を変更した後に接続の中断を停止する方法はありますか？それとも、少なくとも実際に動作するcrontab内でsshを使用する方法はありますか？
マシンはUbuntu 16.04です。
まず、ありがとうございます。
編集：これは、停止したSSHで-vフラグを使用して生成されたログです。
OpenSSH_7.2p2 Ubuntu-4ubuntu2.4, OpenSSL 1.0.2g 1 Mar 2016
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "x.x.x.x" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to x.x.x.x [x.x.x.x] port 22.
debug2: fd 3 setting O_NONBLOCK
debug1: fd 3 clearing O_NONBLOCK
debug1: Connection established.
debug3: timeout: 9999 ms remain after connect
debug1: permanently_set_uid: 0/0
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/known_hosts type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/known_hosts-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.4
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu2.4
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu2.4 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to x.x.x.x:22 as 'user'
debug3: hostkeys_foreach: reading file "/root/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /root/.ssh/known_hosts:1
debug3: record_hostkey: found key type RSA in file /root/.ssh/known_hosts:2
debug3: record_hostkey: found key type ED25519 in file /root/.ssh/known_hosts:3
debug3: load_hostkeys: loaded 3 keys from x.x.x.x
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug3: send packet: type 20
debug1: SSH2_MSG_KEXINIT sent
debug3: receive packet: type 20
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: [email protected],[email protected],[email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected],zlib
debug2: compression stoc: none,[email protected],zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected]
debug2: compression stoc: none,[email protected]
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: [email protected]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug3: send packet: type 30
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug3: receive packet: type 31
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:6GY6MDJn0TC3fXnid2v8CJIe918ZFkC6yxQ+jugNUwE
debug3: hostkeys_foreach: reading file "/root/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /root/.ssh/known_hosts:1
debug3: record_hostkey: found key type RSA in file /root/.ssh/known_hosts:2
debug3: record_hostkey: found key type ED25519 in file /root/.ssh/known_hosts:3
debug3: load_hostkeys: loaded 3 keys from x.x.x.x
debug1: Host 'x.x.x.x' is known and matches the ECDSA host key.
debug1: Found key in /root/.ssh/known_hosts:1
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug2: set_newkeys: mode 0
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /root/.ssh/known_hosts ((nil)), explicit
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred gssapi-keyex,gssapi-with-mic,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: Trying private key: /root/.ssh/known_hosts