> Source: [sk185250](https://support.checkpoint.com/results/sk/sk185250)
# sk185250 - Anti-Spoofing Drops Valid Traffic on Cluster
| Property | Value |
|----------|-------|
| Solution ID | sk185250 |
| Date Created | 2026-08-09 |
| Last Modified | 2026-08-11 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
## Symptoms
- * Anti-Spoofing drops occur although the affected interface is configured correctly.
* Incorrect Anti-Spoofing ranges appear for the affected interface.
To see the ranges, on the affected Security Gateway or each affected Cluster Mode, run in Expert mode:
`fwaccel ranges`
## Cause
The issue occurs when the Cluster object in SmartConsole contains an interface name mismatch between the actual Gaia OS interface name and the interface name stored in the Advanced interface configuration.
For example, the Gaia OS interface name can be one interface, but the Advanced configuration can reference a different bond or VLAN interface. In the screenshot above, the configuration for eth0 contained Advanced configuration values that referenced bond2.121. Because Anti-Spoofing enforcement is based on interface topology, this mismatch can cause the Security Gateway to compile and enforce Anti-Spoofing topology with incorrect interface-to-network mappings.
## Solution
This solution requires authentication. Please log in to view the full solution.
---
# Agent Instructions
This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.
## Navigating This Knowledge Base
- **Complete index**: [llms.txt](https://support.checkpoint.com/llms.txt)
- **All SK articles**: [SecureKnowledge Sitemap](https://support.checkpoint.com/sitemaps/secureknowledge-sitemap-index.xml)
- **SK article URL pattern**: `https://support.checkpoint.com/results/sk/{skId}`
- **Markdown responses**: AI bot User-Agents automatically receive `text/markdown` content