Почему не удается авторизоваться на сервере по ключу?

Не помогает, все тоже самое.

$ ls ../../.ssh/ -alt
total 49
drwxr-xr-x 1 admin 197121 0 апр 20 16:44 ./
drwxr-xr-x 1 admin 197121 0 апр 20 16:44 tmp/
-rw-r--r-- 1 admin 197121 46 апр 20 16:44 desktop.ini
-rw-r--r-- 1 admin 197121 395 апр 20 15:21 known_hosts
-rw-r--r-- 1 admin 197121 2701 апр 17 10:49 id_rsa.ppk
-rw-r--r-- 1 admin 197121 755 апр 10 13:11 id_rsa.pub
-rw-r--r-- 1 admin 197121 3243 апр 10 13:11 id_rsa
drwxr-xr-x 1 admin 197121 0 апр 4 10:30 ../

.
.
.
debug1: rekey after 4294967296 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /c/Users/admin/.ssh/id_rsa (0x60006be80)
debug2: key: /c/Users/admin/.ssh/id_dsa (0x0)
debug2: key: /c/Users/admin/.ssh/id_ecdsa (0x0)
debug2: key: /c/Users/admin/.ssh/id_ed25519 (0x0)
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /c/Users/admin/.ssh/id_rsa
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg ssh-rsa blen 535
debug2: input_userauth_pk_ok: fp SHA256:1jkaS90EgABQYpRJ1Ijx/HjUD2tM8zC6Zk/3fmi4xKs
debug1: Authentications that can continue: publickey,password
debug1: Trying private key: /c/Users/admin/.ssh/id_dsa
debug1: Trying private key: /c/Users/admin/.ssh/id_ecdsa
debug1: Trying private key: /c/Users/admin/.ssh/id_ed25519
debug2: we did not send a packet, disable method
debug1: Next authentication method: password

$ ssh-copy-id root@
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/c/Users/admin/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@'s password:

$ ssh 'root@'
root@'s password:

А если явно указать ключ?
ssh -i ./id_rsa root@ip

И не забывайте про права:
chmod 600 ./id_rsa

Заодно давайте попробуем посмотреть -vvv

zmd, Сгенерил новый ключ на сервере ssh-keygen -t rsa -b 4096 -C ""
Перенес на локалку , убрал старые ключи

ls -alt ~/.ssh/
total 46
drwxr-xr-x 1 admin 197121 0 апр 23 10:29 ./
-rw-r--r-- 1 admin 197121 395 апр 23 10:28 known_hosts
-rw-r--r-- 1 admin 197121 3243 апр 23 10:24 den
-rw-r--r-- 1 admin 197121 755 апр 23 10:24 den.pub
drwxr-xr-x 1 admin 197121 0 апр 23 10:22 tmp/
-rw-r--r-- 1 admin 197121 46 апр 20 16:44 desktop.ini
drwxr-xr-x 1 admin 197121 0 апр 4 10:30 ../

и запустил $ ssh -i ~/.ssh/den -vvv root@123.4.5.6

OpenSSH_7.3p1, OpenSSL 1.0.2k 26 Jan 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: ssh_connect_direct: needpriv 0
debug1: Connection established.
debug1: identity file /c/Users/admin/.ssh/den type 1
debug1: key_load_public: No such file or directory
debug1: identity file /c/Users/admin/.ssh/den-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.3
debug1: Remote protocol version 2.0, remote software version PaloAltoNetworks_0.2
debug1: no match: PaloAltoNetworks_0.2
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 159.65.88.223:22 as 'root'
debug3: hostkeys_foreach: reading file "/c/Users/admin/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /c/Users/admin/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from 159.65.88.223
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug3: send packet: type 20
debug1: SSH2_MSG_KEXINIT sent
debug3: receive packet: type 20
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: ssh-rsa-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519
debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,zlib@openssh.com,zlib
debug2: compression stoc: none,zlib@openssh.com,zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1
debug2: host key algorithms: ssh-rsa,ssh-dss
debug2: ciphers ctos: aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,aes192-cbc,aes256-cbc
debug2: ciphers stoc: aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,aes192-cbc,aes256-cbc
debug2: MACs ctos: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: MACs stoc: hmac-md5,hmac-sha1,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: compression ctos: none
debug2: compression stoc: none
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: diffie-hellman-group-exchange-sha256
debug1: kex: host key algorithm: ssh-rsa
debug1: kex: server->client cipher: aes128-ctr MAC: hmac-sha1 compression: none
debug1: kex: client->server cipher: aes128-ctr MAC: hmac-sha1 compression: none
debug3: send packet: type 34
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(2048<7680<8192) sent
debug3: receive packet: type 31
debug1: got SSH2_MSG_KEX_DH_GEX_GROUP
debug2: bits set: 1010/2048
debug3: send packet: type 32
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug3: receive packet: type 33
debug1: got SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: ssh-rsa SHA256:eV2G75OFxp2rnZHd2i32/ZhB31WdnvQ08InYJQX+uuc
debug3: hostkeys_foreach: reading file "/c/Users/admin/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /c/Users/admin/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from
debug1: Host is known and matches the RSA host key.
debug1: Found key in /c/Users/admin/.ssh/known_hosts:1
debug2: bits set: 1051/2048
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey after 4294967296 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug2: set_newkeys: mode 0
debug1: rekey after 4294967296 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /c/Users/admin/.ssh/den (0x60006bd20), explicit
debug3: send packet: type 5
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /c/Users/admin/.ssh/den
debug3: send_pubkey_test
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 60
debug1: Server accepts key: pkalg ssh-rsa blen 535
debug2: input_userauth_pk_ok: fp SHA256:Ysdtf/XGf9pIm/ikIQwZXWxEaRhX6yoVi5Xg5zTYN6g
debug3: sign_and_send_pubkey: RSA SHA256:Ysdtf/XGf9pIm/ikIQwZXWxEaRhX6yoVi5Xg5zTYN6g
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,password
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password

Вряд ли это является причиной ошибки "incorrect signature".

1. Сгенерил на сервере, куда пытаюсь попасть, все равно не получается.

2. Я на винде же тут такая команда не дает нужного результата.