最近少し食べました。私の考えでは、問題はPamに関連しているようです。しかし、何らかの理由でログイン試行の間にはまだ遅延がありません。
周りを見回すと、人々は待ち時間が長すぎるという正反対の問題だけを持っているようです。
私の考えでは、この遅延はpamにハードコードされており、sshd_configにリンクされていますが、そこには何もありません。
どこを見るべきかについてのアドバイスをいただきありがとうございます。 pamとsshdに加えて、このプロセスには何が含まれていますか？これはセキュリティ侵害の兆候かもしれません（いつものように奇妙なIPがたくさん訪れています）。システムを再インストールする必要がありますか？
遅延は他の場所に存在し、ssh'ingが消えた場合にのみ発生します。
/etc/ssh/sshd_config:
# $OpenBSD: sshd_config,v 1.95 2015/04/27 21:42:48 djm Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin
# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options override the
# default value.
#Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::
# The default requires explicit activation of protocol 1
#Protocol 2
# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_dsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
#HostKey /etc/ssh/ssh_host_ed25519_key
# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 1024
# Ciphers and keying
#RekeyLimit default none
# Logging
# obsoletes QuietMode and FascistLogging
#SyslogFacility AUTH
#LogLevel INFO
# Authentication:
#LoginGraceTime 2m
PermitRootLogin no
#StrictModes yes
#MaxAuthTries 3
#MaxSessions 2
#RSAAuthentication yes
#PubkeyAuthentication yes
# The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
# but this is overridden so installations will only check .ssh/authorized_keys
AuthorizedKeysFile .ssh/authorized_keys
#AuthorizedPrincipalsFile none
#AuthorizedKeysCommand none
#AuthorizedKeysCommandUser nobody
# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#RhostsRSAAuthentication no
# similar for protocol version 2
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# RhostsRSAAuthentication and HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes
# To disable tunneled clear text passwords, change to no here!
#PasswordAuthentication yes
#PermitEmptyPasswords no
# Change to no to disable s/key passwords
ChallengeResponseAuthentication no
# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
#AllowAgentForwarding yes
#AllowTcpForwarding yes
#GatewayPorts no
#X11Forwarding no
#X11DisplayOffset 10
#X11UseLocalhost yes
#PermitTTY yes
PrintMotd no # pam does that
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
UsePrivilegeSeparation sandbox # Default for new installations.
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none
# no default banner path
#Banner none
# override default of no subsystems
Subsystem sftp /usr/lib/ssh/sftp-server
# Example of overriding settings on a per-user basis
#Match User anoncvs
# X11Forwarding no
# AllowTcpForwarding no
# PermitTTY no
# ForceCommand cvs server
cat /etc/pam.d/*:
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
account required pam_permit.so
password include system-auth
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_unix.so sha512 shadow
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
account required pam_permit.so
password include system-auth
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth required pam_securetty.so
auth requisite pam_nologin.so
auth include system-local-login
account include system-local-login
session include system-local-login
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_unix.so sha512 shadow
#%PAM-1.0
auth required pam_unix.so
account required pam_unix.so
password required pam_unix.so
session required pam_unix.so
#%PAM-1.0
#password required pam_cracklib.so difok=2 minlen=8 dcredit=2 ocredit=2 retry=3
#password required pam_unix.so sha512 shadow use_authtok
password required pam_unix.so sha512 shadow nullok
#%PAM-1.0
# For root login to succeed here with pam_securetty, "rlogin" must be
# listed in /etc/securetty.
auth required pam_nologin.so
auth required pam_securetty.so
auth required pam_env.so
auth sufficient pam_rhosts.so
auth include system-auth
account include system-auth
password include system-auth
session optional pam_keyinit.so force revoke
session required pam_loginuid.so
session include system-auth
#%PAM-1.0
# For root login to succeed here with pam_securetty, "rsh" must be
# listed in /etc/securetty.
auth required pam_nologin.so
auth required pam_securetty.so
auth required pam_env.so
auth required pam_rhosts.so
account include system-auth
session optional pam_keyinit.so force revoke
session required pam_loginuid.so
session include system-auth
auth required pam_unix.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
#auth required pam_securetty.so #disable remote root
auth include system-remote-login
account include system-remote-login
password include system-remote-login
session include system-remote-login
#%PAM-1.0
auth sufficient pam_rootok.so
# Uncomment the following line to implicitly trust users in the "wheel" group.
#auth sufficient pam_wheel.so trust use_uid
# Uncomment the following line to require a user to be in the "wheel" group.
#auth required pam_wheel.so use_uid
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
#%PAM-1.0
auth sufficient pam_rootok.so
# Uncomment the following line to implicitly trust users in the "wheel" group.
#auth sufficient pam_wheel.so trust use_uid
# Uncomment the following line to require a user to be in the "wheel" group.
#auth required pam_wheel.so use_uid
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
#%PAM-1.0
auth include system-auth
account include system-auth
session include system-auth
#%PAM-1.0
auth required pam_unix.so try_first_pass nullok
auth optional pam_permit.so
auth required pam_env.so
account required pam_unix.so
account optional pam_permit.so
account required pam_time.so
password required pam_unix.so try_first_pass nullok sha512 shadow
password optional pam_permit.so
session required pam_limits.so
session required pam_unix.so
session optional pam_permit.so
#%PAM-1.0
auth include system-login
account include system-login
password include system-login
session include system-login
#%PAM-1.0
auth required pam_tally.so onerr=succeed file=/var/log/faillog
auth required pam_shells.so
auth requisite pam_nologin.so
auth include system-auth
account required pam_access.so
account required pam_nologin.so
account include system-auth
password include system-auth
session optional pam_loginuid.so
session include system-auth
session optional pam_motd.so motd=/etc/motd
session optional pam_mail.so dir=/var/spool/mail standard quiet
-session optional pam_systemd.so
session required pam_env.so
#%PAM-1.0
auth include system-login
account include system-login
password include system-login
session include system-login
#%PAM-1.0
auth sufficient pam_permit.so
account include system-auth
session optional pam_loginuid.so
session required pam_limits.so
session required pam_unix.so
session optional pam_permit.so
session required pam_env.so
# This file is part of systemd.
#
# Used by systemd --user instances.
account include system-login
session include system-login
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_unix.so
account required pam_unix.so
session required pam_unix.so
password required pam_permit.so
いつものように、追加情報が必要な場合はお知らせください。