zsp@zspdeAir ~ % ssh user@192.168.10.21 -p 24770
Warning: Permanently added '[192.168.10.21]:24770' (ED25519) to the list of known hosts.

解决：
ubuntu server

 ssh -o PubkeyAcceptedKeyTypes=+ssh-rsa user@192.168.23.21

openwrt

ssh -o HostKeyAlgorithms=+ssh-rsa -o PubkeyAcceptedKeyTypes=+ssh-rsa root@192.168.23.1

一劳永逸 配置~/.ssh/config

Host * # 配置全局
    ServerAliveInterval 120
    TCPKeepAlive no
    IPQoS=throughput
    StrictHostKeyChecking no
    HostKeyAlgorithms +ssh-rsa
    PubkeyAcceptedKeyTypes +ssh-rsa
    UserKnownHostsFile=/dev/null

Host github.com
        IdentityFile ~/.ssh/github

Host op 192.168.23.1 # 指定局部
        HostName 192.168.23.1
        User root
        HostKeyAlgorithms +ssh-rsa
        PubkeyAcceptedKeyTypes +ssh-rsa
        IdentityFile ~/.ssh/id_rsa