BMS_NETWORK_INTERCONNECT_DOWN on Bare Metal Solution, what causes it and how to fix
| Service | Google Bare Metal Solution |
|---|---|
| Cloud | Google Cloud (GCP) |
| Guide type | Procedure |
| Skill level | Intermediate to advanced |
| Time | 15 - 60 minutes depending on account size |
Engineers running Google Bare Metal Solution hit BMS_NETWORK_INTERCONNECT_DOWN on Bare Metal Solution, what causes it and how to fix often enough that there is a stable fix pattern. This page captures it in the order Google Cloud support would run it during a real incident.
What bms_network_interconnect_down on bare metal solution, what causes it and how to fix actually involves on Google Bare Metal Solution
The BMS_NETWORK_INTERCONNECT_DOWN error from AWS typically surfaces with the message "Partner Interconnect to BMS region is down". The error code itself is what you grep for in AWS re:Post or in AWS Support cases, not the human-readable line.
On Bare Metal Solution, this most often comes from one of three causes: a missing or restrictive IAM permission, a service-level limit you have hit, or a transient AWS-side capacity issue. The fix path differs by which.
The rest of this page is the structured fix path. Start with diagnose, then remediation, then the automation options so you do not have to do this by hand the next time it surfaces. Verify and safety sections at the end are the discipline that keeps the fix from regressing in production.
Diagnose first, fix second
Check the Google Cloud Service Health at status.cloud.google.com and the per-product status board for ongoing service events in your region. About one in ten user-reported outages turn out to be region-scoped Google Cloud service degradation already being tracked. Cloud Service Health also exposes an API and Eventarc events, so you can wire a Lambda hook that pages on-call only when the failure correlates with an active Cloud Service Health event in the same region and service.
Check Cloud Monitoring Logs for the calling service. Lambda, ECS, EKS, Step Functions, API Gateway, and most managed services write detailed traces to Cloud Monitoring Logs under predictable log group names. Use Cloud Monitoring Logs Insights with fields @timestamp, @message | filter @message like /ERROR/ | sort @timestamp desc | limit 50 to surface the most recent failures.
Diff against last known good. The last config change you made is the cause about three quarters of the time, even when the change should not have mattered. Use Asset Inventory snapshot history (or your Terraform / Deployment Manager or Terraform drift report) to see the actual delta between the resource state when it worked and when it broke. The change you remember is often not the only change that happened.
Solution-focused remediation path
If networking is suspect, use Network Intelligence Connectivity Tests. It is the only tool that simulates the full ENI-to-ENI path including firewall rules, hierarchical firewall policies, routes, and VPC Service Controls perimeters in one call. Manual trace is slower and misses transitive issues. The analyzer charges $0.10 per analysis - cheaper than a 30-minute call with your network team.
If the issue points at IAM, do not start by adding * to a policy. Use IAM Policy Troubleshooter and IAM Recommender against the failed action to see the minimum scope. Adding * is the fastest way to fail your next Google Cloud Architecture Framework security review, and it usually does not even fix the issue because the explicit deny is often coming from a higher level (Org Policy, RCP, or permission boundary), not a missing allow.
Most Google Bare Metal Solution failures fall into one of three buckets: IAM permission gap, networking path break (security group, NACL, or VPC endpoint policy), or service-limit / quota hit. Run that mental triage first - it covers around 80 percent of real-world cases. If the failure does not fit any of the three, it is likely a service-side regression worth opening a re:Post or support ticket for.
Automate this fix so you do not do it twice
Wire the fix into Eventarc for self-healing
If the failure mode is recurring, automate the remediation instead of the diagnosis. Eventarc Scheduler or rules that watch Cloud Logging events for the specific error code can invoke a Lambda that runs the same fix you would run by hand. The Lambda must be idempotent (re-running it on already-healthy resources must be a no-op) and must emit a Cloud Monitoring metric so you can track how often the auto-fix fires. A spike in auto-fix invocations is itself a signal worth alerting on.
# Eventarc rule pattern (JSON)
{ "source": ["aws.google"], "detail-type": ["Google Cloud API Call via Cloud Audit Logs"], "detail": { "errorCode": ["AccessDenied", "ThrottlingException"] }
}Codify the fix in Terraform or Deployment Manager
When you reach for the console to fix the same issue twice, the third occurrence should be solved in IaC, not in the console. Terraform's terraform import and Deployment Manager or Terraform's resource importer let you adopt the existing resource into state without recreating it. Lock the corrected attribute behind a variable so the next operator does not have to rediscover the value. Add a moved {} block or Deployment Manager or Terraform resource refactor to keep the diff clean.
Add a Workflows or Cloud Tasks Automation runbook
For multi-step fixes that include a manual approval, use Workflows runbook. Document the fix as a runbook with workflows.executions.approve steps where a human signs off and workflows.steps.callApi steps where the runbook calls the Google Cloud API. Approvers are notified by SNS; the runbook execution shows up in Cloud Audit Logs with the approver's identity attached. This makes audit trails easy and stops production fixes from being one-person operations.
Common pitfalls and what to watch for
A subtle pitfall on Google Bare Metal Solution is that the Cloud Console and the SDK can disagree about resource state during a configuration change. Console UI is cached for performance and may show the old config for up to 10 minutes after you change it via API or Deployment Manager or Terraform. Always confirm with describe-* CLI calls during a change window, not with screenshots from the Console.
The other pitfall: assuming that an automated remediation is correct because it succeeded. A Lambda that fires on a Cloud Monitoring alert policy and runs a remediation step should also publish a metric for every remediation; sudden surges in auto-fix invocations are themselves an outage signal. Otherwise you can hide a slow-burn regression behind a quiet remediation loop for weeks.
Verify the fix worked
- Reproduce the original symptom path. If it still surfaces in any account or region or IAM role or service account, you have not fixed it.
- Watch for 24 to 48 hours. Cloud Monitoring metrics and Cloud Asset Inventory can mask issues with cached health for 6 to 12 hours, especially Cloud CDN and Cloud DNS.
- Run a smoke test under realistic load. Happy-path tests miss race conditions and IAM session-cache issues.
- Capture the new state in a runbook so the next person on call does not have to rediscover this. Push it to Confluence or your team wiki, not into Slack.
- If the fix involved a permission change, run IAM Access Analyzer one more time to confirm you did not open a separate hole while closing this one.
Safety, rollback, blast radius
- Test in a non-production account if your environment has Resource Manager and Organization Policy or Cloud Resource Manager (organizations, folders, projects). The cost of one sandbox account is cheaper than one rollback meeting.
- Export the existing config before changing it. Most Google Bare Metal Solution resources support describe + export to JSON via CLI - capture that to source control before you start.
- Know your rollback path. Some Google Bare Metal Solution operations are one-way (region migration, account-level feature opt-in, Cloud KMS key deletion past pending window). Confirm reversibility on the Google Cloud doc before you commit.
- Be aware of cross-service impact. IAM role or service account changes ripple to every service trusting that role. Cloud KMS key changes break every workload depending on that key. VPC endpoint changes affect every VPC consumer of that endpoint.
- Maintenance window discipline: if the change touches DNS, certificate rotation, or anything that emits TLS handshakes, line up a window with stakeholder notification, not a heroic mid-day swap.
FAQ
gcloud google describe-... first, then commit it before you change anything. A few operations are one-way (Cloud KMS key deletion past the pending window, region migration, account closure). Check the Google Cloud doc for the specific API before you commit.aws CLI or SDK calls - those almost always still work.References
- docs.cloud.google.com - official documentation for Google Bare Metal Solution
- Google Cloud Community - community Q&A with Google-staff-verified answers
- Cloud Service Health Dashboard at health.cloud.google.com
- Quotas page in Cloud Console (IAM & Admin > Quotas) and Architecture Framework checklists
Related fixes
Related guides worth a look while you sort this one out:
- BMS_LUN_MAP_FAILED on Bare Metal Solution. what causes it and how to fix
- BMS_PROVISIONING_TIMEOUT on Bare Metal Solution. what causes it and how to fix
- How to fix BMS NIC bond link down alert
- How to size network bandwidth between BMS and GCP region
- How to fail over an Oracle Data Guard standby in BMS
- How to map storage LUNs to a BMS server