> Source: [sk31821](https://support.checkpoint.com/results/sk/sk31821)

# sk31821 - Traffic that is sent to Secondary IP addresses / Alias IP addresses that were defined on interfaces of ClusterXL members is not processed

| Property | Value |
|----------|-------|
| Solution ID | sk31821 |
| Date Created | 2006-06-09 |
| Last Modified | 2017-11-15 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Linux, Gaia |

## Symptoms

- A Secondary IP address / Alias IP address that has been defined on physical interface(s) of ClusterXL members and has been defined in Topology of cluster object does not work - the traffic that is sent to this Secondary IP address is not processed by the cluster.

## Cause

This behaviour is by design.

Check Point ClusterXL does not support Secondary IP addresses / Alias IP.

## Solution

No fix is required, since the system is functioning as designed.

If the physical machine, which serves as a cluster member does not have enough physical interfaces, then VLAN interfaces should be configured.

**Related solutions:**

* [sk89980 - Support for Sub-interfaces / Alias IP address / Secondary IP address in Check Point products](http://supportcontent.checkpoint.com/solutions?id=sk89980)
* [sk43451 - Are sub-interfaces supported in IPSO VRRP cluster?](http://supportcontent.checkpoint.com/solutions?id=sk43451)

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