> Source: [sk65560](https://support.checkpoint.com/results/sk/sk65560)

# sk65560 - The 'cphaprob -a if' command shows 'Inbound: UP, Outbound: DOWN'

| Property | Value |
|----------|-------|
| Solution ID | sk65560 |
| Date Created | 2011-10-18 |
| Last Modified | 2021-03-11 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * Output of the `cphaprob state` command shows that a ClusterXL member is `Down`.

* Output of the `cphaprob -a if` command shows "`Inbound: UP , Outbound: DOWN`".

  <br />

## Cause

Physical/Logical connectivity issue due to one of the following:

1. Bad switch configuration (factors such as: Speed, Duplex, Flow Control, etc).
2. Bad network cable.
3. Bad switch port (if it is a copper port, verify that that are no bent or missing pins in the socket).
4. High latency on switch (switch might be under heavy load or have poor connection).
5. Bad port on appliance (if it is a copper port, verify that there are no bent or missing pins in the socket).
6. Subnet mis-match between cluster members on the interface shown to have the issue.
7. Mismatch in monitor mode - monitor mode is not supported in ClusterXL
8. Anti-Spoofing is not configured correctly.
9. IGMP Membership issues (often occurs with Nexus switches)
10. Network Adapter LAN segment (when working with Virtual Machines) are mismatched between cluster members.
11. Cluster ID is already in use

![](https://sc1.checkpoint.com/sc/SolutionsStatics/sk65560/LAN Segment1701122349.png)

## Solution

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

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