我试图在每次重新启动时使用Cron来启动autossh连接。
启动它的命令是以下自动连接：
autossh -M 0 -N -q -o ServerAliveInterval=20 -o ServerAliveCountMax=3 3 HMzg8fspYGfW11oJ7Jl6bkDnT2lYrB@fw1.sshreach.me -i prvtkey2.pem -R 13532:localhost:22 -v
我将此命令放入start-autossh.sh内名为/home/debian的bash脚本中。 prvtkey.pem私钥也位于此文件夹中。我使用Cron重新启动时启动此脚本，如下所示：
@reboot 30;cd /home/debian && sh start-autossh.sh
起初效果不错。但是，当我重新启动系统时，它不起作用。以下是连接成功与失败（重新启动后）时来自autossh的日志。
我想知道重启是否实际上不能正常终止当前的autossh连接，因此，当启动后尝试重新连接时，服务器会拒绝。如果这是问题所在，我如何确保autossh连接在重新启动时被正确终止？
自动连接成功后：
OpenSSH_7.4p1 Debian-10+deb9u4, OpenSSL 1.0.2l 25 May 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to fw1.sshreach.me [139.162.161.211] port 22.
debug1: Connection established.
debug1: key_load_public: No such file or directory
debug1: identity file prvtkey2.pem type -1
debug1: key_load_public: No such file or directory
debug1: identity file prvtkey2.pem-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.4p1 Debian-10+deb9u4
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6
debug1: match: OpenSSH_6.6 pat OpenSSH_6.5*,OpenSSH_6.6* compat 0x14000000
debug1: Authenticating to fw1.sshreach.me:22 as
'HMzg8fspYGfW11oJ7Jl6bkDnT2lYrB'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: algorithm: ecdh-sha2-nistp256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC:
<implicit> compression: none
debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC:
<implicit> compression: none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256
SHA256:nCeg0Bt8GiwhKOuEf4Q72pWxxjasEIbxm4yRhAqgkos
debug1: Host 'fw1.sshreach.me' is known and matches the ECDSA host key.
debug1: Found key in /home/debian/.ssh/known_hosts:3
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Trying private key: prvtkey2.pem
debug1: Authentication succeeded (publickey).
Authenticated to fw1.sshreach.me ([139.162.161.211]:22).
debug1: Remote connections from LOCALHOST:13532 forwarded to local address
localhost:22
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug1: pledge: network
debug1: Remote: Forwarding listen address "localhost" overridden by server
GatewayPorts
debug1: remote forward success for: listen 13532, connect localhost:22
debug1: All remote forwarding requests processed
当autossh连接失败时，重新引导后（它停留在SSH2_MSG_KEXINIT发送状态）：
OpenSSH_7.4p1 Debian-10+deb9u4, OpenSSL 1.0.2l 25 May 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to fw1.sshreach.me [139.162.161.211] port 22.
debug1: Connection established.
debug1: key_load_public: No such file or directory
debug1: identity file prvtkey2.pem type -1
debug1: key_load_public: No such file or directory
debug1: identity file prvtkey2.pem-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.4p1 Debian-10+deb9u4
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6
debug1: match: OpenSSH_6.6 pat OpenSSH_6.5*,OpenSSH_6.6* compat 0x14000000
debug1: Authenticating to fw1.sshreach.me:22 as
'HMzg8fspYGfW11oJ7Jl6bkDnT2lYrB'
debug1: SSH2_MSG_KEXINIT sent