> Source: [sk180394](https://support.checkpoint.com/results/sk/sk180394)

# sk180394 - Session Initiation Protocol (SIP) traffic causes the Security Gateway to freeze

| Property | Value |
|----------|-------|
| Solution ID | sk180394 |
| Date Created | 2022-12-13 |
| Last Modified | 2024-12-10 |
| Technical Level | General |
| Products | Security Gateway, Scalable Platforms |
| Versions | R81.20, R81.10 (EOS), R81 (EOS), R81.20, R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- SIP traffic causes the Security Gateway to freeze (for example: a VoIP phone joins or initiates a connection).
**Notes** :

* A hard reboot of the appliance resolves the issue.
* This issue applies to all Gateway solutions (examples: Maestro, Cloud, Open Server).

## Cause

An error occurred in the SIP MultiCore functionality.

<br />

## Solution

This problem was fixed. The fix is included starting from:

* [Check Point R82](https://support.checkpoint.com/results/sk/sk181127)
* [Jumbo Hotfix Accumulator for R81.20](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.20/Default.htm) starting from Take 8
* [Jumbo Hotfix Accumulator for R81.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.10/Default.htm) starting from Take 93
* [Jumbo Hotfix Accumulator for R81](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81/Default.htm) starting from Take 82
* [Jumbo Hotfix Accumulator for R80.40](https://sc1.checkpoint.com/documents/Jumbo_HFA/R80.40/Default.htm) starting from Take 196

Check Point recommends to always upgrade to the [Recommended version](https://support.checkpoint.com/results/sk/sk95746) ([Security Gateway](https://support.checkpoint.com/product/73) / [VSX](https://support.checkpoint.com/product/359) / [Security Management Server](https://support.checkpoint.com/product/184) / [Multi-Domain Security Management Server](https://support.checkpoint.com/product/166) / [SmartConsole](https://support.checkpoint.com/product/191)).

If you choose not to upgrade, [contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for your version.

A Support Engineer will make sure the Hotfix is compatible with your environment before providing it.  
For faster resolution and verification, collect these files:

1. [CPinfo](https://support.checkpoint.com/results/sk/sk92739) file from the Management Server involved in the case.
2. [CPinfo](https://support.checkpoint.com/results/sk/sk92739) file from the Security Gateway / each Cluster Member involved in the case.

**Hotfix installation instructions:**   
Refer to [sk168597 - How to install a Hotfix](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk168597).  

As a **workaround**, disable the VoIP SIP MultiCore feature:

**Note** - This feature improves the Security Gateway's performance in R80.40 and higher by inspecting SIP traffic in all CoreXL Firewall instances (and not only in the global CoreXL Firewall instance #0).

1. Connect to the command line on the Security Gateway / each Cluster Member.

2. Log in.

3. Run the applicable command:

   |--------------|---------------------------------------|----------------------------------------|
   | Operation    | For How Long?                         | Command                                |
   | Disable      | Temporarily (does not survive reboot) | `fw ctl set int sip_is_multicore 0`    |
   | Disable      | Permanently (survives reboot)         | `fw ctl set -f int sip_is_multicore 0` |
   | Enable Again | Temporarily (does not survive reboot) | `fw ctl set int sip_is_multicore 1`    |
   | Enable Again | Permanently (survives reboot)         | `fw ctl set -f int sip_is_multicore 1` |

<br />

---

# Agent Instructions

This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.

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