OpenShell/deploy/rpm/CONFIGURATION.md

OpenShell Gateway Configuration (RPM)

Configuration reference for the OpenShell gateway when installed via the RPM package on Fedora and RHEL systems.

For first-time setup, see QUICKSTART.md. For troubleshooting, see TROUBLESHOOTING.md.

Default configuration

The RPM ships a default TOML configuration template at /usr/share/openshell-gateway/gateway.toml.default. On first start of openshell-gateway.service, the systemd unit copies this template to ~/.config/openshell/gateway.toml if no config file exists there yet.

The defaults are tuned for rootless Podman use:

[openshell]
version = 1

[openshell.gateway]
bind_address = "0.0.0.0:17670"
compute_drivers = ["podman"]

bind_address = "0.0.0.0:17670" is required because Podman sandbox containers reach the gateway over the host network bridge and cannot connect to 127.0.0.1 inside the gateway's network namespace. mTLS is enabled by default and protects all connections.

compute_drivers = ["podman"] pins the compute driver to Podman. Without this, the gateway auto-detects in order: Kubernetes, Podman, Docker. Pinning prevents unexpected driver selection if Docker is also installed on the host.

Customizing the configuration

Edit ~/.config/openshell/gateway.toml directly. The template at /usr/share/openshell-gateway/gateway.toml.default is not read at runtime and is not overwritten by RPM upgrades.

To apply environment variable overrides that persist across upgrades without editing the TOML file, add them to ~/.config/openshell/gateway.env:

# Example: restrict to loopback only
OPENSHELL_BIND_ADDRESS=127.0.0.1

To override the path to the TOML config file entirely:

# In ~/.config/openshell/gateway.env
OPENSHELL_GATEWAY_CONFIG=/path/to/custom/gateway.toml

For one-off service overrides that persist across package upgrades:

systemctl --user edit openshell-gateway

TLS (mTLS)

The RPM enables mutual TLS by default. The gateway requires a valid client certificate for all API connections and listens on 0.0.0.0:17670 by default (see "Default configuration" above).

Auto-generated certificates

On first start, the systemd user service runs openshell-gateway generate-certs --output-dir ~/.local/state/openshell/tls --server-san host.openshell.internal to generate certificates with rcgen (the same routine the CLI uses for local mTLS bundles):

File	Purpose	Location
CA certificate	Root of trust	~/.local/state/openshell/tls/ca.crt
CA private key	Signs server and client certs	~/.local/state/openshell/tls/ca.key
Server certificate	Gateway TLS identity	~/.local/state/openshell/tls/server/tls.crt
Server private key	Gateway TLS key	~/.local/state/openshell/tls/server/tls.key
Client certificate	CLI and sandbox identity	~/.local/state/openshell/tls/client/tls.crt
Client private key	CLI and sandbox key	~/.local/state/openshell/tls/client/tls.key

Client certificates are also copied to the CLI auto-discovery directory:

~/.config/openshell/gateways/openshell/mtls/
  ca.crt
  tls.crt
  tls.key

The CLI automatically discovers these certificates when connecting to a gateway on localhost or 127.0.0.1.

Server certificate SANs

The auto-generated server certificate includes these Subject Alternative Names:

• localhost
• openshell
• openshell.openshell.svc
• openshell.openshell.svc.cluster.local
• host.containers.internal
• host.docker.internal
• host.openshell.internal
• 127.0.0.1

To connect from a remote machine, you need externally-managed certificates with additional SANs. See "Remote CLI access" in TROUBLESHOOTING.md.

Using externally-managed certificates

To use certificates from an external CA or cert-manager:

1. Place the server cert, key, and CA cert on the filesystem.

2. Edit ~/.config/openshell/gateway.toml:

   [openshell.gateway.tls]
   cert_path = "/path/to/server/tls.crt"
   key_path = "/path/to/server/tls.key"
   client_ca_path = "/path/to/ca.crt"
   

3. Place the client cert where the CLI expects it:

   ~/.config/openshell/gateways/openshell/mtls/
     ca.crt
     tls.crt
     tls.key
   

Rotating certificates

Delete the TLS state directory and restart the gateway:

rm -rf ~/.local/state/openshell/tls
systemctl --user restart openshell-gateway

The gateway regenerates the PKI on next start.

Disabling TLS

WARNING: With TLS disabled, the gateway API has no authentication. Keep the bind address on 127.0.0.1, or place the gateway behind a TLS-terminating reverse proxy that enforces its own authentication.

To disable TLS (not recommended for production):

1. Edit ~/.config/openshell/gateway.toml:

   [openshell.gateway]
   disable_tls = true
   

2. Remove or comment out the guest_tls_* entries in ~/.config/openshell/gateway.toml if they are set.

3. Restart the gateway.

Sandbox TLS

When mTLS is enabled, the Podman driver bind-mounts the client certificates into each sandbox container so the supervisor process can establish an mTLS connection back to the gateway.

The following TOML fields control the host-side paths of the client certificates that are mounted into sandbox containers:

[openshell.gateway]
guest_tls_ca = "/home/user/.local/state/openshell/tls/ca.crt"
guest_tls_cert = "/home/user/.local/state/openshell/tls/client/tls.crt"
guest_tls_key = "/home/user/.local/state/openshell/tls/client/tls.key"

Inside the container, the supervisor reads them from:

• /etc/openshell/tls/client/ca.crt
• /etc/openshell/tls/client/tls.crt
• /etc/openshell/tls/client/tls.key

On SELinux-enabled systems, the Podman driver automatically applies the :z relabel option to these bind mounts. No manual SELinux configuration is required.

Configuration reference

Gateway and driver settings have local runtime defaults. The gateway reads ~/.config/openshell/gateway.toml when that file exists. Set OPENSHELL_GATEWAY_CONFIG in the launch environment to use a different file.

Use systemctl --user edit openshell-gateway for service environment overrides that persist across package upgrades.

Gateway settings

TOML option	Default	Description
bind_address	0.0.0.0:17670 (RPM default)	Address for the gRPC/HTTP API.
compute_drivers	["podman"] (RPM default)	When unset, the gateway auto-detects Kubernetes, then Podman, then Docker. The RPM default pins to Podman.
default_image	ghcr.io/nvidia/openshell-community/sandboxes/base:latest	Default sandbox image.
supervisor_image	ghcr.io/nvidia/openshell/supervisor:latest	Supervisor image mounted into Podman sandboxes.
guest_tls_ca, guest_tls_cert, guest_tls_key	auto-generated paths	Client TLS material bind-mounted into sandbox containers.
[openshell.gateway.tls] paths	auto-generated paths	Server TLS certificate, key, and client CA.
disable_tls	unset	Set to true to disable TLS.

The database URL is not accepted in TOML. When OPENSHELL_DB_URL is unset, the gateway uses sqlite:$XDG_STATE_HOME/openshell/gateway/openshell.db.

Driver TOML settings

Create ~/.config/openshell/gateway.toml when you need to customize driver settings:

[openshell]
version = 1

[openshell.gateway]
bind_address = "0.0.0.0:17670"
compute_drivers = ["podman"]
default_image = "ghcr.io/nvidia/openshell-community/sandboxes/base:latest"

[openshell.drivers.podman]
image_pull_policy = "missing"
network_name = "openshell"
stop_timeout_secs = 10

Image management

The gateway pulls container images automatically on first sandbox creation. The default pull policy is missing, which means images are pulled once and then cached by Podman.

To update cached images:

podman pull ghcr.io/nvidia/openshell/supervisor:latest
podman pull ghcr.io/nvidia/openshell-community/sandboxes/base:latest

Or set image_pull_policy = "always" in [openshell.drivers.podman] to pull on every sandbox creation.

To pin specific image versions instead of :latest:

supervisor_image = "ghcr.io/nvidia/openshell/supervisor:v0.0.37"
default_image = "ghcr.io/nvidia/openshell-community/sandboxes/base:v0.0.37"

For air-gapped environments:

1. On a connected machine, pull and save the images:

   podman pull ghcr.io/nvidia/openshell/supervisor:latest
   podman pull ghcr.io/nvidia/openshell-community/sandboxes/base:latest
   podman save -o supervisor.tar ghcr.io/nvidia/openshell/supervisor:latest
   podman save -o sandbox.tar ghcr.io/nvidia/openshell-community/sandboxes/base:latest
   

2. Transfer the tarballs to the air-gapped host and load them:

   podman load -i supervisor.tar
   podman load -i sandbox.tar
   

3. Set pull policy to never:

   [openshell.drivers.podman]
   image_pull_policy = "never"
   

File locations

Purpose	Path
Gateway binary	/usr/bin/openshell-gateway
CLI binary	/usr/bin/openshell
Systemd user unit	/usr/lib/systemd/user/openshell-gateway.service
Default TOML config template (read-only)	/usr/share/openshell-gateway/gateway.toml.default
Active gateway TOML configuration	~/.config/openshell/gateway.toml
Optional environment variable overrides	~/.config/openshell/gateway.env
TLS certificates	~/.local/state/openshell/tls/
CLI client certs	~/.config/openshell/gateways/openshell/mtls/
Gateway database	~/.local/state/openshell/gateway/openshell.db