[Linux](EN) Access server via proxy server or jump host server using SSH ProxyJump

Access server via proxy server or jump host using ProxyJump

Environment and Prerequisite

• Linux
• SSH

ProxyJump

Purpose

Many systems use proxy or jump host to connect production server due to security. It is comfortable to use ProxyJump rather than use ssh command separately.

Usage

• Format

Host [proxy server name]
    HostName [proxy or jump host domain or ip address]
    Port [port number]
    User [username]
    IdentityFile [proxy or jump host identity key file]

Host [remote server name]
    HostName [server domain or ip address]
    Port [port number]
    User [username]
    IdentityFile [server identity key file]
    ProxyJump [proxy server name]

Example

• Local -> proxy-server -> remote-server
• Both IdentityFile should be located in Local.
• Below case is only for example. In real production, Local -> proxy-server is usually public network and proxy-server -> remote-server is usually private network.

Host proxy-server
    HostName 192.168.64.3
    Port 22
    User twpower
    IdentityFile ~/.ssh/proxy-server

Host remote-server
    HostName 192.168.64.4
    Port 22
    User twpower
    IdentityFile ~/.ssh/remote-server
    ProxyJump proxy-server

• Access direct to remote-server

ssh remote-server

Reference

• https://man.openbsd.org/ssh_config.5#ProxyJump