Virtual Private Cloud Flow Logs Extended to Cross-Cloud Networks
Gaining Greater Visibility into Network Traffic Across Hybrid and Cross‑Cloud Environments
In modern hybrid environments — where infrastructure spans on‑premises data centers and multiple cloud providers — clear visibility into network traffic is essential.
VPC Flow Logs have long provided detailed traffic records for Google Cloud subnets. But as network topologies become more complex with solutions like the Cross‑Cloud Network, the need for broader monitoring has grown.
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New Capabilities for Flow Logs
You can now enable VPC Flow Logs directly on:
- Cloud VPN tunnels
- VLAN attachments (for Cloud Interconnect and Cross‑Cloud Interconnect)
This enhancement allows comprehensive monitoring of traffic between on‑premises systems, other clouds, and Google Cloud.
Benefits
- Granular insights: Capture logs for network flows with full 5‑tuple details (source/destination IP, source/destination port, protocol).
- Performance optimization: Identify “elephant flows” that could be congesting a VPN tunnel or VLAN attachment for better capacity planning.
- Shared VPC auditing: Determine which service projects consume the most hybrid bandwidth.
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Practical Use Cases
These improvements support:
- Mapping utilization to flows
- Correlate high‑level bandwidth graphs with specific application flows to understand usage.
- Diagnosing connectivity issues
- Verify if on‑premises or cross‑cloud traffic reaches its Google Cloud gateway (VLAN attachment or VPN tunnel).
- Tuning Cloud Interconnect QoS policies
- Validate that applications set the correct DSCP markings.
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Gateway Annotations in Flow Logs
To add context, gateway annotations are now part of VPC Flow Logs. A gateway is the ingress or egress point between your Google Cloud VPC and an external network.
Key New Fields
- `reporter` – Indicates traffic direction relative to a gateway:
- `SRC_GATEWAY`: Traffic entering Google Cloud via Cloud Interconnect or VPN (on‑premises → Google Cloud)
- `DEST_GATEWAY`: Traffic exiting Google Cloud via Cloud Interconnect or VPN (Google Cloud → on‑premises)
- `gateway` object – A JSON payload containing:
- Name
- Type (`VPN_TUNNEL` or `INTERCONNECT_ATTACHMENT`)
- Project ID
- Location
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Analyze Logs with Flow Analyzer
Flow Analyzer integrates gateway annotations to make traffic analysis easier — no complex SQL required.
With Flow Analyzer, you can:
- Identify top talkers at 5‑tuple granularity
- Run connectivity tests to assess configuration impact
- Use Gemini Cloud Assist for natural language queries
- Compare current vs. historical flows (hour/day/week)
Flow Analyzer showing Cloud Interconnect traffic insights
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How This Integrates with AI‑Powered Publishing Workflows
For teams wanting cross‑platform distribution of network analytics or technical reports, open‑source platforms like AiToEarn官网 can complement these capabilities:
- Generates AI‑powered content
- Publishes simultaneously to channels like Douyin, Kwai, WeChat, Bilibili, Rednote, Facebook, Instagram, LinkedIn, Threads, YouTube, Pinterest, and X (Twitter)
- Provides analytics and AI model ranking for growth strategy
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Activating Flow Logs for Cross‑Cloud Network
To gain visibility:
- Enable VPC Flow Logs on VLAN attachments and VPN tunnels for both new and existing connections.
- Use:
- CLI
- API
- Terraform
- Google Cloud Console
For detailed instructions, see:
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Bottom line:
By enabling VPC Flow Logs for your hybrid connections, you gain critical telemetry — essential for managing, securing, and scaling complex cross‑cloud networks. Combined with analytics tools and publishing platforms like AiToEarn, network teams can deliver insight‑rich, multi‑channel reports efficiently.
