User Specific SSH Configuration Files

17th chunk of `ssh.man`

b255b6c4e2ec7c10136aa7e2e938fcd3b105aa047490cb5e0000000100000e2e

 others.

       ~/.shosts
               This file is used in exactly the same way as .rhosts, but allows
               host‐based  authentication   without   permitting   login   with
               rlogin/rsh.

       ~/.ssh/
               This  directory  is  the  default location for all user‐specific
               configuration and authentication information.  There is no  gen‐
               eral  requirement  to keep the entire contents of this directory
               secret, but the recommended permissions  are  read/write/execute
               for the user, and not accessible by others.

       ~/.ssh/authorized_keys
               Lists  the  public  keys  (DSA, ECDSA, Ed25519, RSA) that can be
               used for logging in as this user.  The format of  this  file  is
               described  in  the sshd(8) manual page.  This file is not highly
               sensitive, but the recommended permissions  are  read/write  for
               the user, and not accessible by others.

       ~/.ssh/config
               This  is  the  per‐user configuration file.  The file format and
               configuration options are described in  ssh_config(5).   Because
               of  the  potential for abuse, this file must have strict permis‐
               sions: read/write for the user, and not writable by others.   It
               may  be  group‐writable provided that the group in question con‐
               tains only the user.

       ~/.ssh/environment
               Contains additional definitions for environment  variables;  see
               “ENVIRONMENT”, above.

       ~/.ssh/id_dsa
       ~/.ssh/id_ecdsa
       ~/.ssh/id_ecdsa_sk
       ~/.ssh/id_ed25519
       ~/.ssh/id_ed25519_sk
       ~/.ssh/id_rsa
               Contains  the  private key for authentication.  These files con‐
               tain sensitive data and should be readable by the user  but  not
               accessible  by others (read/write/execute).  ssh will simply ig‐
               nore a private key file if it is accessible by  others.   It  is
               possible  to  specify a passphrase when generating the key which
               will be used to encrypt the sensitive part of  this  file  using
               AES‐128.

       ~/.ssh/id_dsa.pub
       ~/.ssh/id_ecdsa.pub
       ~/.ssh/id_ecdsa_sk.pub
       ~/.ssh/id_ed25519.pub
       ~/.ssh/id_ed25519_sk.pub
       ~/.ssh/id_rsa.pub
               Contains the public key for authentication.  These files are not
               sensitive and can (but need not) be readable by anyone.

       ~/.ssh/known_hosts
               Contains  a  list of host keys for all hosts the user has logged
               into that are not already in the systemwide list of  known  host
               keys.   See  sshd(8)  for  further details of the format of this
               file.

       ~/.ssh/rc
               Commands in this file are executed by ssh when the user logs in,
               just before the user’s shell (or command) is started.   See  the
               sshd(8) manual page for more information.

       /etc/hosts.equiv
               This  file  is  for  host‐based  authentication (see above).  It
               should only be writable by root.

       /etc/ssh/shosts.equiv
               This file is used in exactly the same way  as  hosts.equiv,  but
               allows  host‐based  authentication without permitting login with
               rlogin/rsh.

       /etc/ssh/ssh_config
               Systemwide configuration file.  The file format  and  configura‐

Title: User Specific SSH Configuration Files

Summary

This section describes user-specific SSH configuration files and their purposes including: ~/.shosts (like .rhosts, but without rlogin/rsh), ~/.ssh/ (default directory for configuration and authentication), ~/.ssh/authorized_keys (public keys for login), ~/.ssh/config (per-user configuration file), ~/.ssh/environment (environment variable definitions), ~/.ssh/id_* (private keys), ~/.ssh/id_*.pub (public keys), ~/.ssh/known_hosts (list of known host keys), and ~/.ssh/rc (commands executed upon login). It also describes system-wide files like /etc/hosts.equiv, /etc/ssh/shosts.equiv and /etc/ssh/ssh_config.