我能够通过 ssh 连接到我的 Centos7 服务器：
ssh [email protected]
我正在尝试安装和配置 Elasticsearch。在执行此操作时，我通过以下命令停止了 eth0：
ifdown eth0
我正在尝试通过 ssh 重新启动 eth0 但没有成功......
当然，通过输入这样的命令
ssh -vvv -p 22 [email protected]
我得到这样的结果：
ssh: connect to host xx.xxx.xx.xxx port 22: Operation timed out
这是通过端口 21 连接的结果：
OpenSSH_8.1p1, LibreSSL 2.7.3
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 47: Applying options for *
debug2: resolve_canonicalize: hostname xx.xxx.xx.xxx is address
debug2: ssh_connect_direct
debug1: Connecting to xx.xxx.xx.xxx [xx.xxx.xx.xxx] port 21.
debug1: Connection established.
debug1: identity file /Users/davide/.ssh/id_rsa type 0
debug1: identity file /Users/davide/.ssh/id_rsa-cert type -1
debug1: identity file /Users/davide/.ssh/id_dsa type -1
debug1: identity file /Users/davide/.ssh/id_dsa-cert type -1
debug1: identity file /Users/davide/.ssh/id_ecdsa type -1
debug1: identity file /Users/davide/.ssh/id_ecdsa-cert type -1
debug1: identity file /Users/davide/.ssh/id_ed25519 type -1
debug1: identity file /Users/davide/.ssh/id_ed25519-cert type -1
debug1: identity file /Users/davide/.ssh/id_xmss type -1
debug1: identity file /Users/davide/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.1
kex_exchange_identification: Connection closed by remote host
我是linux终端的新手，有什么建议吗？