OpenSSH /etc/ssh/ssh_config

Original 📋 Ubuntu 20.04 LTS (Focal Fossa) 52 lines

Details

Size
52 lines
MD5
a3c7f5afdd3660d71549275d5f003476
SHA256
495c3d1d4a9999d869dc693d52d41eef4d28bd22f8bca4864c519bc7db5dff97
/etc/ssh/ssh_config
# This is the ssh client system-wide configuration file.  See
# ssh_config(5) for more information.  This file provides defaults for
# users, and the values can be changed in per-user configuration files
# or on the command line.

# Configuration data is parsed as follows:
#  1. command line options
#  2. user-specific file
#  3. system-wide file
# Any configuration value is only changed the first time it is set.
# Thus, host-specific definitions should be at the beginning of the
# configuration file, and defaults at the end.

# Site-wide defaults for some commonly used options.  For a comprehensive
# list of available options, their meanings and defaults, please see the
# ssh_config(5) man page.

Include /etc/ssh/ssh_config.d/*.conf

Host *
#   ForwardAgent no
#   ForwardX11 no
#   ForwardX11Trusted yes
#   PasswordAuthentication yes
#   HostbasedAuthentication no
#   GSSAPIAuthentication no
#   GSSAPIDelegateCredentials no
#   GSSAPIKeyExchange no
#   GSSAPITrustDNS no
#   BatchMode no
#   CheckHostIP yes
#   AddressFamily any
#   ConnectTimeout 0
#   StrictHostKeyChecking ask
#   IdentityFile ~/.ssh/id_rsa
#   IdentityFile ~/.ssh/id_dsa
#   IdentityFile ~/.ssh/id_ecdsa
#   IdentityFile ~/.ssh/id_ed25519
#   Port 22
#   Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc
#   MACs hmac-md5,hmac-sha1,umac-64@openssh.com
#   EscapeChar ~
#   Tunnel no
#   TunnelDevice any:any
#   PermitLocalCommand no
#   VisualHostKey no
#   ProxyCommand ssh -q -W %h:%p gateway.example.com
#   RekeyLimit 1G 1h
    SendEnv LANG LC_*
    HashKnownHosts yes
    GSSAPIAuthentication yes

Copy & Paste

curl:
curl https://exampleconfig.com/api/v1/config/original/a3c7f5afdd3660d71549275d5f003476?hint=ssh_config
wget:
wget -O ssh_config https://exampleconfig.com/api/v1/config/original/a3c7f5afdd3660d71549275d5f003476?hint=ssh_config

For AI Agents

<prompt><role>DevOps agent</role><source url='https://exampleconfig.com/api/v1/config/original/a3c7f5afdd3660d71549275d5f003476?hint=ssh_config' /><config><app>OpenSSH</app><os>Ubuntu 20.04 LTS (Focal Fossa)</os><location>/etc/ssh/ssh_config</location><lines>52</lines><md5>a3c7f5afdd3660d71549275d5f003476</md5><sha256>495c3d1d4a9999d869dc693d52d41eef4d28bd22f8bca4864c519bc7db5dff97</sha256></config></prompt>

Paste into Claude, ChatGPT, or any AI assistant.

Install OpenSSH

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

File Location

File Path
/etc/ssh/ssh_config
Directory
/etc/ssh/
Significance
System-wide configuration directory
Description
Files in /etc/ contain system-wide configuration settings that affect all users.

FAQ

When should I use this ssh_config?

Use it to restore a missing default, confirm what shipped, or diff against your current OpenSSH config.

How do I restore OpenSSH defaults?

Download the file, back up the current one in /etc/ssh/ssh_config, replace it, then reload or restart OpenSSH.

Is ssh_config safe for production?

It is the vendor default for Ubuntu 20.04 LTS (Focal Fossa). Treat it as a baseline and review security and performance settings before production use.

How does this differ from other OS versions?

Defaults vary by distro and version. This copy matches Ubuntu 20.04 LTS (Focal Fossa).

Can I use this for OpenSSH troubleshooting?

Yes. Diff it against yours to find drift, then restore only the sections you need.