> Source: [sk82840](https://support.checkpoint.com/results/sk/sk82840)

# sk82840 - ClusterXL interface is intermittently reported as 'down'

| Property | Value |
|----------|-------|
| Solution ID | sk82840 |
| Date Created | 2012-08-21 |
| Last Modified | 2015-01-15 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * '`cphaprob state`' command intermittently shows one member as "`Down`".  

* '`cphaprob list`' command intermittently shows that state of '`Interface Active Check`' Device is '`problem`'.  

* '`cphaprob -a if`' command intermittently shows one or more interfaces as "`DOWN`".  

* Traffic capture on the problematic interface (tcpdump/snoop) show series of ARP Requests for IP addresses incrementing sequentially from the first IP address to the last IP address within the subnet of the problematic interface.

## Cause

The problematic interface was configured to be monitored by cluster. Either there is no traffic at all on the problematic interface, or there is a problem with Cluster Control Protocol (CCP) packets on the problematic interface.

## Solution

This solution requires authentication. Please log in to view the full solution.

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