作為一個運維 不是你懂多少知識才是你的價值 你有幸能遇到多少錯誤才是你的最大的價值
知識 你有我有大家有 錯誤我有你沒有 這便是我的價值
我遇到一個錯誤 蠻難遇到的一個錯誤 所以想分享給大家
下面我在模擬機演示給大家 用 root權限 避免你們說是因為權限的錯誤
2017年9月5日 我在切換sftp時候遇到一個錯誤（端口號是22 說寫端口號的閉嘴）
[root@backup ssh]# sftp -oPort=22 root@10.0.0.31
Connecting to 10.0.0.31...
The authenticity of host '10.0.0.31 (10.0.0.31)' can't be established.
RSA key fingerprint is 25:4d:a6:65:1b:77:85:41:f0:18:07:c8:e0:12:c9:9b.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.0.0.31' (RSA) to the list of known hosts.
root@10.0.0.31's password:
subsystem request failed on channel 0
Couldn't read packet: Connection reset by peer
我們來看看這個錯誤
Couldn't read packet: Connection reset by peer
無法讀取數據包:通過對等項重置連接
這是一個很難遇到的錯誤
排查之路：
tail -f /var/log/messages
Sep 5 12:31:53 backup sshd[3131]: subsystem request for sftp failed, subsyst found
Sep 5 12:37:15 backup sshd[3136]: Accepted password for root from 10.0.0.31 9088 ssh2
Sep 5 12:37:15 backup sshd[3136]: subsystem request for sftp
Sep 5 12:37:15 backup sshd[3136]: subsystem request for sftp failed, subsyst found
[root@backup ssh]# rpm -ql openssh-clients
/etc/ssh/ssh_config
/usr/bin/.ssh.hmac
/usr/bin/scp
/usr/bin/sftp
/usr/bin/slogin
/usr/bin/ssh
/usr/bin/ssh-add
/usr/bin/ssh-agent
/usr/bin/ssh-copy-id
[root@backup ssh]# grep sftp /etc/ssh/sshd_config
Subsystem sftp /usr/libexec/openssh/sftp-server
[root@backup ssh]# ll /usr/libexec/openssh/sftp-server
-rwxr-xr-x. 1 root root 67640 Mar 22 16:33 /usr/libexec/openssh/sftp-server
查看文檔
If so, it's the cause of this error message. That's especially true if your sftp user is logging into a chrooted environment, where "/usr/lib" probably does not exist. My own sftp server is configured this way.
However, SSHD has the sftp functionality built-in and does not need to execute an external "helper" program like that. So, if you have a line like the above, it can be fixed by changing it to:
如果是，這是錯誤消息的原因。尤其是，如果您的sftp用戶登錄到一個chrooted環境，其中“/ usr /lib”可能不存在。我自己的sftp服務器是這樣配置的。
但是，sshd具有內置的sftp功能，不需要執行像這樣的外部“助手”程序。因此，如果您有類似上述的行，可以通過將其更改為:
錯誤解決邏輯圖
