For starters, I won't have physical access to this machine for about a month, so I'm looking for a way to remotely reboot it. I've ssh'd to it dozens of times in the past, but it seems like it booted up cranky and isn't taking SSH connections. If there is a way to force a reboot without authentication, I'll take that answer too, but I'd like to figure out this SSH error. Tried SSH from MacOSX, Ubuntu, and PuTTY, same result.
Sanitized -vvv log below: Shows one intentional failed password attempt, and then the immediate "connection closed" error upon successful password entry.
OpenSSH_8.1p1, LibreSSL 2.7.3
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 47: Applying options for *
debug1: Connecting to hostname.ddns.net port 22.
debug1: Connection established.
debug1: identity file /Users/user/.ssh/id_rsa type -1
debug1: identity file /Users/user/.ssh/id_rsa-cert type -1
debug1: identity file /Users/user/.ssh/id_dsa type -1
debug1: identity file /Users/user/.ssh/id_dsa-cert type -1
debug1: identity file /Users/user/.ssh/id_ecdsa type -1
debug1: identity file /Users/user/.ssh/id_ecdsa-cert type -1
debug1: identity file /Users/user/.ssh/id_ed25519 type -1
debug1: identity file /Users/user/.ssh/id_ed25519-cert type -1
debug1: identity file /Users/user/.ssh/id_xmss type -1
debug1: identity file /Users/user/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_8.2p1 Ubuntu-4ubuntu0.2
debug1: match: OpenSSH_8.2p1 Ubuntu-4ubuntu0.2 pat OpenSSH* compat 0x04000000
debug3: fd 5 is O_NONBLOCK
debug1: Authenticating to hostname.ddns.net:22 as 'user'
debug3: hostkeys_foreach: reading file "/Users/user/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/user/.ssh/known_hosts:7
debug3: load_hostkeys: loaded 1 keys from hostname.ddns.net
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
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,[email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],[email protected],[email protected],ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected],zlib
debug2: compression stoc: none,[email protected],zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256,[email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256
debug2: host key algorithms: rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected]
debug2: compression stoc: none,[email protected]
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug3: send packet: type 30
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug3: receive packet: type 31
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:iRTQSo4RTdhojOhRyY9wokC3bCgHZCpfEV9g87wJ5jA
debug3: hostkeys_foreach: reading file "/Users/user/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/user/.ssh/known_hosts:7
debug3: load_hostkeys: loaded 1 keys from hostname.ddns.net
debug3: hostkeys_foreach: reading file "/Users/user/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/user/.ssh/known_hosts:7
debug3: load_hostkeys: loaded 1 keys from xx.xx.xx.xx
debug1: Host 'hostname.ddns.net' is known and matches the ECDSA host key.
debug1: Found key in /Users/user/.ssh/known_hosts:7
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey out after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug1: SSH2_MSG_NEWKEYS received
debug2: set_newkeys: mode 0
debug1: rekey in after 134217728 blocks
debug1: Will attempt key: /Users/user/.ssh/id_rsa
debug1: Will attempt key: /Users/user/.ssh/id_dsa
debug1: Will attempt key: /Users/user/.ssh/id_ecdsa
debug1: Will attempt key: /Users/user/.ssh/id_ed25519
debug1: Will attempt key: /Users/user/.ssh/id_xmss
debug2: pubkey_prepare: done
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,[email protected],ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected]>
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: Trying private key: /Users/user/.ssh/id_rsa
debug3: no such identity: /Users/user/.ssh/id_rsa: No such file or directory
debug1: Trying private key: /Users/user/.ssh/id_dsa
debug3: no such identity: /Users/user/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /Users/user/.ssh/id_ecdsa
debug3: no such identity: /Users/user/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /Users/user/.ssh/id_ed25519
debug3: no such identity: /Users/user/.ssh/id_ed25519: No such file or directory
debug1: Trying private key: /Users/user/.ssh/id_xmss
debug3: no such identity: /Users/user/.ssh/id_xmss: No such file or directory
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
[email protected]'s password:
debug3: send packet: type 50
debug2: we sent a password packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,password
Permission denied, please try again.
[email protected]'s password:
debug3: send packet: type 50
debug2: we sent a password packet, wait for reply
Connection closed by xx.xx.xx.xx port 22