Critical capacity alarm for "Tier-1 Logical Routers with NAT Enabled" in VMware NSX Manager

Products

• VMware NSX

Issue/Introduction

You observe a critical capacity alarm on the NSX Manager regarding the "Tier-1 Logical Routers with NAT Enabled" limit.

• The system reports a usage significantly higher than the actual limit while the actual usage is validated to be within normal limits (e.g., ~200 objects).

• This issue is a management plane reporting error and has no impact on production traffic or configuration limits.

You see log entries in /var/log/proton/nsxapi.log indicating the object count is oscillating or "flapping" between the correct and incorrect values:

grep "CapacityUsageStreamListener" /var/log/proton/nsxapi.log | grep "NUMBER_OF_TIER1_WITH_NAT_RULE"

var/log/proton/nsxapi.log:2025-12-19T10:56:38.299Z ... count=0
var/log/proton/nsxapi.log:2025-12-19T10:56:38.456Z ... count=4637
var/log/proton/nsxapi.log:2025-12-19T10:56:38.751Z ... count=200

Environment

VMware NSX

Resolution

To resolve this issue, you must clear the memory state on the affected NSX Manager node.

1. Log in to the CLI of the affected NSX Manager (the node reporting the false positive).

2. Restart the manager service with the following command:

   restart service manager