Technologies/Tailscale/tailscale.subnet_router.routes.approved
TailscaleTailscaleMetric

tailscale.subnet_router.routes.approved

Approved subnet routes
Dimensions:None
Available on:DatadogDatadog (1)

Summary

Number of subnet routes that have been administratively approved for this device to route traffic for. Approved routes are actively used for forwarding decisions in the tailnet. Low counts relative to advertised routes indicate pending approval backlogs blocking connectivity. Zero values despite advertisements mean no subnet routing is active. Critical for validating subnet router configuration and ensuring intended routing topology is operational.

Interface Metrics (1)
DatadogDatadog
Number of approved subnet routes
Dimensions:None
Sources
tailscale.subnet_router.approved_routesdocs.datadoghq.com

Technical Annotations (19)

Configuration Parameters (2)
net.ipv4.ip_forwardrecommended: 1
must be enabled on subnet router for forwarding
tailscale.web.portrecommended: 5252
required ACL port for remote metrics collection over tailnet
Error Signatures (1)
subnetIPForwardingNotEnablederror code
CLI Commands (7)
tailscale metrics printdiagnostic
ip route showdiagnostic
tailscale status --json | jq '.Self.PrimaryRoutes, .Self.AdvertisedRoutes'diagnostic
sysctl -w net.ipv4.ip_forward=1remediation
tailscale metrics writemonitoring
curl 100.100.100.100/metricsdiagnostic
tailscale webmonitoring
Technical References (9)
exit nodecomponentsubnet routercomponentIP forwardingconceptDERP relaycomponentsubnet routeconcepttailscale0component100.100.100.100componenttextfile collectorcomponentsubnet routerscomponent
Related Insights (9)
Local area network access failure through subnet routerwarning
▸
Exit node or subnet router offline blocks connectivitycritical
▸
Subnet router IP forwarding not enabled blocks subnet accesscritical
▸
Tailscale client metrics available for Prometheus scrapinginfo
▸
Subnet route overlaps with existing routes causing unexpected routing behaviorwarning
▸
Subnet router lacks IP forwarding or firewall rules preventing traffic flowcritical
▸
Subnet router health monitoring requires metrics collection setupinfo
▸
Subnet routes advertised but not approved blocks expected traffic routingwarning
▸
Subnet router routes pending approval blocking connectivitywarning

When a subnet router advertises routes that remain unapproved, devices attempting to reach those subnets will fail to establish connectivity. This represents a configuration gap between advertised network capabilities and operational reality, often caused by approval workflow delays or miscommunication.

▸