OpenSSH /etc/ssh/sshd_config

Original 📋 Debian 9 (Stretch) 123 Zeilen
/etc/ssh/sshd_config
#	$OpenBSD: sshd_config,v 1.100 2016/08/15 12:32:04 naddy 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 ::

#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
#HostKey /etc/ssh/ssh_host_ed25519_key

# Ciphers and keying
#RekeyLimit default none

# Logging
#SyslogFacility AUTH
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
#PermitRootLogin prohibit-password
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

#PubkeyAuthentication yes

# Expect .ssh/authorized_keys2 to be disregarded by default in future.
#AuthorizedKeysFile	.ssh/authorized_keys .ssh/authorized_keys2

#AuthorizedPrincipalsFile none

#AuthorizedKeysCommand none
#AuthorizedKeysCommandUser nobody

# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# 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 yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no

# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
#GSSAPIStrictAcceptorCheck yes
#GSSAPIKeyExchange no

# 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 yes
#X11DisplayOffset 10
#X11UseLocalhost yes
#PermitTTY yes
PrintMotd no
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#UsePrivilegeSeparation sandbox
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /var/run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none

# no default banner path
#Banner none

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

# override default of no subsystems
Subsystem	sftp	/usr/lib/openssh/sftp-server

# Example of overriding settings on a per-user basis
#Match User anoncvs
#	X11Forwarding no
#	AllowTcpForwarding no
#	PermitTTY no
#	ForceCommand cvs server

Kopieren & Einfügen

curl:
curl https://exampleconfig.com/api/v1/config/original/bbad7ed242a834e831c7066901cee49e?hint=sshd_config
wget:
wget -O sshd_config https://exampleconfig.com/api/v1/config/original/bbad7ed242a834e831c7066901cee49e?hint=sshd_config

Für KI-Agenten

<prompt><role>DevOps agent</role><source url='https://exampleconfig.com/api/v1/config/original/bbad7ed242a834e831c7066901cee49e?hint=sshd_config' /><config><app>OpenSSH</app><os>Debian 9 (Stretch)</os><location>/etc/ssh/sshd_config</location><lines>123</lines><md5>bbad7ed242a834e831c7066901cee49e</md5><sha256>8431c6f565a1a13e95982597051796c564d265706cbce797e33ac223ef136383</sha256></config></prompt>

Füge es in Claude, ChatGPT oder einen anderen KI-Assistenten ein.

OpenSSH installieren

Alpine Linux

sudo apk add openssh-server

Debian

sudo apt update && sudo apt install openssh-server

Red Hat Enterprise Linux

sudo yum install openssh-server

Ubuntu

sudo apt update && sudo apt install openssh-server

Ablageort

Pfad
/etc/ssh/sshd_config
Verzeichnis
/etc/ssh/
Bedeutung
Systemweites Konfig-Verzeichnis
Beschreibung
In /etc/ liegen systemweite Einstellungen, die alle Benutzer betreffen.

FAQ

Wann sollte ich sshd_config verwenden?

Nutze sie, um eine fehlende Default-Datei wiederherzustellen, zu prüfen, was ausgeliefert wurde, oder sie gegen deine aktuelle OpenSSH-Config zu diffen.

Wie stelle ich die Defaults von OpenSSH wieder her?

Lad die Datei runter, sichere die aktuelle in /etc/ssh/sshd_config, ersetze sie und lade OpenSSH neu oder starte es neu.

Ist sshd_config für den produktiven Einsatz geeignet?

Das ist der Hersteller-Default für Debian 9 (Stretch). Nimm sie als Basis und prüf Security- und Performance-Einstellungen, bevor du sie produktiv nutzt.

Wie unterscheidet sich das von anderen OS-Versionen?

Defaults variieren je nach Distro und Version. Diese Version passt zu Debian 9 (Stretch).

Kann ich das fürs Troubleshooting von OpenSSH nutzen?

Ja. Diff es gegen deine Version, finde Abweichungen und stell nur die Teile wieder her, die du brauchst.