No puedo conectarme al servidor ssh, el cliente se bloquea permanentemente, no puedo iniciar sesión

No puedo conectarme al servidor ssh, el cliente se bloquea permanentemente, no puedo iniciar sesión

Intento acceder a un servidor mediante ssh desde mi computadora portátil y mi teléfono. Ambos se cuelgan al intentar conectarse. He incluido registros del servidor y del cliente, pero no veo nada que me ayude a comprender cuál es el problema.

Salida del cliente:

╭─fenton@ss9 ~ ‹master*›
╰─$ ssh -vvv dell
OpenSSH_8.1p1, OpenSSL 1.1.1d  10 Sep 2019
debug1: Reading configuration data /home/fenton/.ssh/config
debug1: /home/fenton/.ssh/config line 2: Applying options for dell
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: resolve_canonicalize: hostname 192.168.1.20 is address
debug2: ssh_connect_direct
debug1: Connecting to dell [192.168.1.20] port 22.
debug1: Connection established.
debug1: identity file /home/fenton/.ssh/id_rsa type 0
debug1: identity file /home/fenton/.ssh/id_rsa-cert type -1
debug1: identity file /home/fenton/.ssh/id_dsa type -1
debug1: identity file /home/fenton/.ssh/id_dsa-cert type -1
debug1: identity file /home/fenton/.ssh/id_ecdsa type -1
debug1: identity file /home/fenton/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/fenton/.ssh/id_ed25519 type -1
debug1: identity file /home/fenton/.ssh/id_ed25519-cert type -1
debug1: identity file /home/fenton/.ssh/id_xmss type -1
debug1: identity file /home/fenton/.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_8.1
debug1: match: OpenSSH_8.1 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.1.20:22 as 'fenton'
debug3: hostkeys_foreach: reading file "/home/fenton/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/fenton/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from 192.168.1.20
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,diffie-hellman-group14-sha1
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:MCd1xJqd/iYfOFjfp2wotdb1RrqJwxaIZrQADw0cMHk
debug3: hostkeys_foreach: reading file "/home/fenton/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/fenton/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from 192.168.1.20
debug1: Host '192.168.1.20' is known and matches the ECDSA host key.
debug1: Found key in /home/fenton/.ssh/known_hosts:55
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: /home/fenton/.ssh/id_rsa RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug1: Will attempt key: /home/fenton/.ssh/id_dsa
debug1: Will attempt key: /home/fenton/.ssh/id_ecdsa
debug1: Will attempt key: /home/fenton/.ssh/id_ed25519
debug1: Will attempt key: /home/fenton/.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,ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521>
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 public key: /home/fenton/.ssh/id_rsa RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 60
debug1: Server accepts key: /home/fenton/.ssh/id_rsa RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug3: sign_and_send_pubkey: RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug3: sign_and_send_pubkey: signing using rsa-sha2-512
debug3: send packet: type 50
debug3: receive packet: type 52
debug1: Authentication succeeded (publickey).
Authenticated to 192.168.1.20 ([192.168.1.20]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug3: send packet: type 90
debug1: Requesting [email protected]
debug3: send packet: type 80
debug1: Entering interactive session.
debug1: pledge: network
debug3: receive packet: type 80
debug1: client_input_global_request: rtype [email protected] want_reply 0
debug3: receive packet: type 4
debug1: Remote: /home/fenton/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
debug3: receive packet: type 4
debug1: Remote: /home/fenton/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
debug3: receive packet: type 91
debug2: channel_input_open_confirmation: channel 0: callback start
debug2: fd 3 setting TCP_NODELAY
debug3: ssh_packet_set_tos: set IP_TOS 0x48
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug3: send packet: type 98
debug2: channel 0: request shell confirm 1
debug3: send packet: type 98
debug2: channel_input_open_confirmation: channel 0: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768

Salida del servidor:

╭─fenton@dell ~ ‹master*› 
╰─$ sudo /usr/bin/sshd -d -D                                                                                                                                                            255 ↵

debug1: sshd version OpenSSH_8.1, OpenSSL 1.1.1d  10 Sep 2019
debug1: private host key #0: ssh-rsa SHA256:5nVbVja+G//lvdDltSTweh9I/EfuwPWn8OZE9hl8HZU
debug1: private host key #1: ecdsa-sha2-nistp256 SHA256:MCd1xJqd/iYfOFjfp2wotdb1RrqJwxaIZrQADw0cMHk
debug1: private host key #2: ssh-ed25519 SHA256:g2eFNxcBFlT/KH9QIfK5pA1KqGw9eq4ThJLjku3pn88
debug1: rexec_argv[0]='/usr/bin/sshd'
debug1: rexec_argv[1]='-d'
debug1: rexec_argv[2]='-D'
debug1: Set /proc/self/oom_score_adj from 0 to -1000
debug1: Bind to port 22 on 0.0.0.0.
Server listening on 0.0.0.0 port 22.
debug1: Bind to port 22 on ::.
Server listening on :: port 22.
debug1: Server will not fork when running in debugging mode.
debug1: rexec start in 5 out 5 newsock 5 pipe -1 sock 8
debug1: inetd sockets after dupping: 3, 3
Connection from 192.168.1.72 port 44554 on 192.168.1.20 port 22 rdomain ""
debug1: Local version string SSH-2.0-OpenSSH_8.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_8.1
debug1: match: OpenSSH_8.1 pat OpenSSH* compat 0x04000000
debug1: permanently_set_uid: 65534/65534 [preauth]
debug1: list_hostkey_types: rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256,ssh-ed25519 [preauth]
debug1: SSH2_MSG_KEXINIT sent [preauth]
debug1: SSH2_MSG_KEXINIT received [preauth]
debug1: kex: algorithm: curve25519-sha256 [preauth]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256 [preauth]
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none [preauth]
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none [preauth]
debug1: expecting SSH2_MSG_KEX_ECDH_INIT [preauth]
debug1: rekey out after 134217728 blocks [preauth]
debug1: SSH2_MSG_NEWKEYS sent [preauth]
debug1: Sending SSH2_MSG_EXT_INFO [preauth]
debug1: expecting SSH2_MSG_NEWKEYS [preauth]
debug1: SSH2_MSG_NEWKEYS received [preauth]
debug1: rekey in after 134217728 blocks [preauth]
debug1: KEX done [preauth]
debug1: userauth-request for user fenton service ssh-connection method none [preauth]
debug1: attempt 0 failures 0 [preauth]
debug1: PAM: initializing for "fenton"
debug1: PAM: setting PAM_RHOST to "192.168.1.72"
debug1: PAM: setting PAM_TTY to "ssh"
debug1: userauth-request for user fenton service ssh-connection method publickey [preauth]
debug1: attempt 1 failures 0 [preauth]
debug1: userauth_pubkey: test pkalg rsa-sha2-512 pkblob RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo [preauth]
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /home/fenton/.ssh/authorized_keys
debug1: fd 4 clearing O_NONBLOCK
debug1: /home/fenton/.ssh/authorized_keys:1: matching key found: RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug1: /home/fenton/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
Accepted key RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo found at /home/fenton/.ssh/authorized_keys:1
debug1: restore_uid: 0/0
Postponed publickey for fenton from 192.168.1.72 port 44554 ssh2 [preauth]
debug1: userauth-request for user fenton service ssh-connection method publickey [preauth]
debug1: attempt 2 failures 0 [preauth]
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /home/fenton/.ssh/authorized_keys
debug1: fd 4 clearing O_NONBLOCK
debug1: /home/fenton/.ssh/authorized_keys:1: matching key found: RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug1: /home/fenton/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
Accepted key RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo found at /home/fenton/.ssh/authorized_keys:1
debug1: restore_uid: 0/0
debug1: auth_activate_options: setting new authentication options
debug1: do_pam_account: called
Accepted publickey for fenton from 192.168.1.72 port 44554 ssh2: RSA SHA256:/hy19zobmQxJ1V5twvfR6E+rPqPeuP+APgtk4R1cLzo
debug1: monitor_child_preauth: fenton has been authenticated by privileged process
debug1: auth_activate_options: setting new authentication options [preauth]
debug1: monitor_read_log: child log fd closed
debug1: PAM: establishing credentials
User child is on pid 1071
debug1: PAM: establishing credentials
debug1: permanently_set_uid: 1000/1000
debug1: rekey in after 134217728 blocks
debug1: rekey out after 134217728 blocks
debug1: ssh_packet_set_postauth: called
debug1: active: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
debug1: Entering interactive session for SSH2.
debug1: server_init_dispatch
debug1: server_input_channel_open: ctype session rchan 0 win 1048576 max 16384
debug1: input_session_request
debug1: channel 0: new [server-session]
debug1: session_new: session 0
debug1: session_open: channel 0
debug1: session_open: session 0: link with channel 0
debug1: server_input_channel_open: confirm session
debug1: server_input_global_request: rtype [email protected] want_reply 0
debug1: server_input_channel_req: channel 0 request pty-req reply 1
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req pty-req
debug1: Allocating pty.
debug1: session_new: session 0
debug1: session_pty_req: session 0 alloc /dev/pts/0
debug1: server_input_channel_req: channel 0 request shell reply 1
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req shell
Starting session: shell on pts/0 for fenton from 192.168.1.72 port 44554 id 0
debug1: Setting controlling tty using TIOCSCTTY.

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