Deploy on VMs - Hilt Documentation

Host resources

The DMG Collector installs a small set of files on the host:

Path	Purpose
`/usr/local/bin/dag-agent`	Static collector binary
`/etc/systemd/system/dag-agent.service`	systemd unit file
`/etc/systemd/system/dag-agent.service.d/limits.conf`	Optional CPU / memory limits drop-in
`/etc/dag-agent/config.yaml`	Configuration
`/var/log/dag-agent/events.jsonl`	Event output file (if file mode)

Installation

The collector can be installed interactively (recommended for first setup) or non-interactively for automation.

Interactive install

tar xzf dag-agent-v<X>-linux-<arch>.tar.gz
cd dag-agent-v<X>-linux-<arch>

./dag-agent -V
sudo ./install.sh

The installer runs a short configuration wizard:

Prompt	Typical answer
Ship URL	PrivateLink destination of control plane (empty for file mode)
JSON output path	`/var/log/dag-agent/events.jsonl` (default), or empty if ship-only
Node label	Defaults to `$(hostname)`
CPU limit	e.g. `20%`, optional
Memory limit	e.g. `512M`, optional
Ring buffer size	`1M` (default) up to `16M` on busy hosts

On submission the installer:

Verifies environment requirements (exits with a clear error otherwise).
Validates connectivity to SHIP_URL.
Installs the binary, writes the unit file + optional limits drop-in, creates the log directory, and starts the service.

Non-interactive / automation install

For config management (Ansible, SSM, cloud-init, Packer), either pre-seed environment variables or install directly:

install -m 755 dag-agent /usr/local/bin/dag-agent
install -m 644 dag-agent.service /etc/systemd/system/dag-agent.service

mkdir -p /etc/dag-agent /var/log/dag-agent

cat > /etc/dag-agent/config.yaml <<'YAML'
ship_url: "https://<name>-ingest.hilt.ai/ingest"
output_path: "/var/log/dag-agent/events.jsonl"
node_id: "${NODE_ID}"
YAML

# Optional limits
mkdir -p /etc/systemd/system/dag-agent.service.d
cat > /etc/systemd/system/dag-agent.service.d/limits.conf <<'UNIT'
[Service]
CPUQuota=20%
MemoryMax=512M
UNIT

systemctl daemon-reload
systemctl enable --now dag-agent

Service configuration

The systemd unit (dag-agent.service) is minimal:

[Unit]
Description=Hilt Collector - eBPF Telemetry Sensor
After=network.target

[Service]
Type=simple
ExecStart=/usr/local/bin/dag-agent
ExecReload=/bin/kill -HUP $MAINPID
Restart=on-failure
RestartSec=5
StandardOutput=journal
StandardError=journal
LimitMEMLOCK=infinity

[Install]
WantedBy=multi-user.target

LimitMEMLOCK=infinity is required for BPF map allocations. If restricted by policy, set it to the expected total map size (~4 MB with default configuration).

Verification

sudo systemctl status dag-agent
sudo journalctl -u dag-agent --no-pager -n 20

Expected output:

dag-agent v<X> starting
Ship mode: https://<name>-ingest.hilt.ai/ingest
BPF object loaded; attached N programs

Upgrade

In-place upgrade consists of replacing the binary and restarting the service:

sudo install -m 755 dag-agent /usr/local/bin/dag-agent
sudo systemctl restart dag-agent

For fleet upgrades, a shell script is included (deploy/ci-install.sh), which assumes a node has already been bootstrapped with install.sh once and only does the binary-swap + restart (no wizard). Typical wiring:

AWS SSM Run Command: Execute across a tag selector (Role=agent, Env=prod) with a one-liner that pulls the new tarball and runs the shell.
Ansible / Salt: Treat /usr/local/bin/dag-agent as a managed file sourced from your artifact cache.
Packer / Image Builder: Bake the agent into a base AMI and roll via your usual image replacement process.

Uninstall

sudo ./uninstall.sh

Removes service and binary, preserves logs. No reboot required.