Today, after upgrading Manjaro, the most basic ssh login suddenly had issues, and the prompts were as follows:

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Unable to negotiate with UNKNOWN port 65535: no matching host key type found. Their offer: ssh-rsa,ssh-dss
lost connection

sign_and_send_pubkey: no mutual signature supported

Upon investigation, I found out…well, OpenSSH deems the ssh-rsa encryption method insecure and has directly disabled this key type for logins by default starting from 8.8…

When using a Linux system, it’s often necessary to set up things that start automatically at boot. For distributions that use systemd, writing your own service files and enabling them is a great choice.