> Source: [sk152552](https://support.checkpoint.com/results/sk/sk152552)

# sk152552 - BGP peer stuck in Active state after upgrade to R80.20

| Property | Value |
|----------|-------|
| Solution ID | sk152552 |
| Date Created | 2019-04-29 |
| Last Modified | 2019-05-02 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * After an upgrade to R80.20, BGP peer is stuck in the Active state (previous versions did not exhibit these symptoms).
* After reverting to R77.30, BGP instantly started working.

## Cause

The peer router is not RFC complaint. It is sending us the ASPATH in 4-byte format, even though the peer does not provide us 4 byte AS capability.

It works with R77.30 because the neighbor does not detect 4 byte AS capability from us. Therefore, it encodes AS number in 2 byte format.

In R80.20, the neighbor detects 4-byte AS capability from us, and therefore encodes AS numbers in 4-byte format without advertising the capability.

## Solution

The problem is not related to Check Point products,

The solution to the problem is to enable 4 byte AS capability on the Devices ( that are peering BGP session with Check Point Security Gateway).

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