煎炸熊の記事本

Source: Unable to add old HostKeyAlgorithms Ciphers KexAlgorithms to sshd_config no hostkey alg error

Source: SSH connection fails with messages “no hostkey alg”

When attempting to establish an SSH connection, you might encounter an error message stating “no hostkey alg”. This is because RHEL 9 only supports SHA2 hashes for RSA host keys, hence they are incompatible with the old linux’s SHA1-based RSA host keys..

However, the old linux can connect to RHEL 9 using ECDSA keys:

ssh -o Hostkeyalgorithms=ecdsa-sha2-nistp256 ServerHostname/ServerIP

You can add the following in /etc/ssh/ssh_config or ~/.ssh/ssh_config:

Host ServerHostname/ServerIP
    Hostkeyalgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521

Source: ssh/sftp no matching cipher found

ssh/sftp 遇到 no matching cipher found 原因是在 OpenSSH 6.7 之後,
預設移除了不安全的 Cipher, *cbc 及 arcfour*
若使用較舊的 Client, 跟 Server 沒有 matching cipher 就會無法連線

解法: 更新 Client或啟用 Server 端不安全的 Cipher,

原文(source): 在VPS上建立最低權限的SSH帳號用於代理服務 | CoCo Bauer

最近基於SSH tunnel的代理方式越來越流行了，本文將教會大家如何在VPS上開設公用SSH帳號用於突破封鎖翻越高牆。方法非常簡單，只要兩步就可以實現：

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