Raw Capture
Raw Capture provides continuous L4 (TCP/UDP) packet capture across all nodes with minimal CPU overhead. It operates independently from L7 dissection and stores all traffic in a node-level FIFO buffer.
Helm Configuration: Control raw capture settings—storage size, capture filters, snapshot storage, and more—via Helm values. See Raw Capture Configuration for details.
Capabilities
| Capability | Description |
|---|---|
| Traffic Snapshots | Extract and preserve traffic for a specific time window |
| PCAP Export | Download raw packets for Wireshark analysis |
| Delayed Dissection | Run L7 protocol analysis on non-production compute |
Architecture
Raw Capture collects data from three layers:
| Layer | Data Collected |
|---|---|
| Network | TCP/UDP packets via eBPF/AF_PACKET |
| Kubernetes | Pod lifecycle, service endpoints, namespace events |
| Operating System | Process context, container IDs via eBPF |
Each worker node writes captured data to a local FIFO buffer. When the buffer reaches capacity, older data is recycled and discarded. To preserve traffic before it’s recycled, create a Traffic Snapshot—the data is moved to dedicated storage where it becomes immutable.
Independence from L7 Dissection
Raw Capture and L7 dissection are controlled separately:
| Setting | Effect |
|---|---|
tap.capture.raw.enabled=true | Raw capture active |
tap.capture.stopped=true | L7 dissection stopped |
Both can run simultaneously, or raw capture can run alone. This enables continuous packet retention with L7 dissection enabled only when needed.
These settings are configured via Helm values. See Raw Capture Configuration for the full configuration reference and Enabling/Disabling Dissection for operational details.
Resource Characteristics
| Metric | Raw Capture | L7 Dissection |
|---|---|---|
| CPU | Low (disk I/O bound) | High (protocol parsing) |
| Memory | Fixed buffer | Scales with traffic |
| Data loss risk | Minimal | Higher under load |
Raw Capture’s low CPU footprint eliminates packet loss under normal conditions. L7 dissection requires more resources but can be deferred to non-production systems.