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# Example configuration for bssh
#
# USER FIELD BEHAVIOR:
# - 'user' in defaults/cluster applies to DESTINATION nodes only
# - For jump hosts, specify username in jump_host string: user@jumphost:port
# - If no username in jump_host, your current local username ($USER) is used
#
# Example:
# user: admin # Used for destination nodes
# jump_host: bai@bastion # User 'bai' for bastion, 'admin' for destination
#
defaults:
user: ubuntu
port: 22
ssh_key: ~/.ssh/id_rsa
parallel: 10
# Global default jump host (optional) - used for all clusters unless overridden
# jump_host: bastion.example.com
clusters:
local:
nodes:
- localhost
user: ${USER}
dev:
nodes:
- dev1.example.com
- dev2.example.com
- dev3.example.com
user: developer
ssh_key: ~/.ssh/dev_key
production:
nodes:
- host: prod1.example.com
port: 2222
user: admin
- host: prod2.example.com
port: 2222
user: admin
# Node-level jump host override (optional)
# jump_host: prod2-bastion.example.com
- host: prod3.example.com
- host: prod4.example.com
ssh_key: ~/.ssh/prod_key
# Cluster-level jump host (optional) - applies to all nodes in this cluster
# jump_host: prod-bastion.example.com
# Example: Cluster behind a jump host/bastion
# IMPORTANT: 'user' field applies to DESTINATION nodes only.
# For jump host authentication, specify username in jump_host string: user@host:port
# If no username is specified in jump_host, your current local username is used.
internal:
nodes:
- host: internal1.private
- host: internal2.private
- host: internal3.private
user: admin # User for internal*.private (destination nodes)
ssh_key: ~/.ssh/destination_key # Key for destination nodes
# Legacy string format (uses cluster ssh_key for both jump host and destinations)
jump_host: jumpuser@bastion.example.com
# Alternative structured format with dedicated jump host key:
# jump_host:
# host: bastion.example.com
# user: jumpuser
# port: 22 # optional
# ssh_key: ~/.ssh/jump_host_key # Uses this key for bastion only
# Example: Mixed direct and jump host access with per-node jump host override
hybrid:
nodes:
- host: behind-firewall.internal
# Per-node jump host with dedicated key
jump_host:
host: gateway.example.com
user: gw_user
ssh_key: ~/.ssh/gateway_key
- host: direct-access.example.com
jump_host: "" # Empty string disables jump host (direct connection)
jump_host: default-bastion.example.com # Default for cluster (string format)
# Example: Multi-hop jump chain with environment variables
secure:
nodes:
- host: target.secure.internal
jump_host: ${FIRST_HOP},${SECOND_HOP} # Comma-separated for multi-hop
# Example: Using SSH config Host alias as jump host
# This references a Host defined in ~/.ssh/config, inheriting its settings:
# - HostName, User, Port, and IdentityFile are all read from SSH config
#
# ~/.ssh/config example:
# Host my-bastion
# HostName bastion.example.com
# User jumpuser
# Port 2222
# IdentityFile ~/.ssh/bastion_key
#
ssh_config_ref:
nodes:
- host: target.internal
# Simple format with @ prefix references SSH config Host alias
jump_host: "@my-bastion"
# Alternative structured format for SSH config reference
ssh_config_ref_structured:
nodes:
- host: target2.internal
jump_host:
ssh_config_host: my-bastion # References SSH config Host alias
# Example: Per-node SSH config references
mixed_ssh_config:
nodes:
- host: node1.internal
jump_host: "@bastion-zone-a" # Different SSH config entry per node
- host: node2.internal
jump_host: "@bastion-zone-b"
- host: node3.internal
# Direct connection, no jump host
jump_host: ""