ssh failing with debug message "no mutual signature algorithm"

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Contents

problem

ssh from a newer client to an older server with rsa keys is failing and asking for a password via the "keyboard-interactive" method.

versions

server openssh version: 6.7_p1 client openssh version: 9.2p1-2

error

when running the ssh command with "-vvv", the following debug message snippet appears...

debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey debug1: Offering public key: /home/jsmith/.ssh/id_rsa.pub RSA SHA256:+untiuu11l/g3ziD0sdffrUHL+JsyasdfYdsXL/OJE explicit
debug1: send_pubkey_test: no mutual signature algorithm
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred: password
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive

solution

add line...

PubkeyAcceptedKeyTypes +ssh-rsa

to file: ~/.ssh/config