Upgrade Hostkey Algorithms

The Client says:

Unable to negotiate with 2a01:foo:bar:baz::cafe port 2222: no matching host key type found. Their offer: ssh-rsa

The Server says:

2021/10/01 22:57:31 modules/ssh/ssh.go:259:sshConnectionFailed() [W] Failed connection from [2a01:foo]:37934 with error: ssh: no common algorithm for host key; client offered: [rsa-sha2-512-cert-v01@openssh.com rsa-sha2-256-cert-v01@openssh.com rsa-sha2-512 rsa-sha2-256 ssh-ed25519-cert-v01@openssh.com ecdsa-sha2-nistp256-cert-v01@openssh.com ecdsa-sha2-nistp384-cert-v01@openssh.com ecdsa-sha2-nistp521-cert-v01@openssh.com sk-ssh-ed25519-cert-v01@openssh.com sk-ecdsa-sha2-nistp256-cert-v01@openssh.com ssh-ed25519 ecdsa-sha2-nistp256 ecdsa-sha2-nistp384 ecdsa-sha2-nistp521 sk-ssh-ed25519@openssh.com sk-ecdsa-sha2-nistp256@openssh.com], server offered: [ssh-rsa]

How can I upgrade my Gitea to work with OpenSSH 8.8 again?

The following may be of assistance: key exhange negotiation failed though client and server share some protocols · Issue #17175 · go-gitea/gitea · GitHub