This document describes the steps to Bypass Microsoft Updates Traffic in Secure Web Appliance (SWA).
Cisco recommends that you have knowledge of these topics:
Cisco recommends that you have these tools installed:
This document is not restricted to specific software and hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, ensure that you understand the potential impact of any command.
Microsoft Updates are essential patches, security updates, and feature enhancements released by Microsoft for its operating systems and software applications. These updates are crucial for maintaining the security, stability, and performance of computers and network devices. They ensure that systems are protected against vulnerabilities, bugs are fixed, and new features or improvements are integrated into the software.
The impact of Microsoft Updates on proxy servers, such as Cisco SWA, can be significant. These updates often involve downloading large files or numerous smaller files, which can consume considerable bandwidth and processing resources on the proxy. This can lead to congestion, slower network performance, and increased load on the proxy infrastructure, potentially affecting the overall user experience and other critical network operations.
Bypassing Microsoft Update traffic from the proxy can be a safe and effective way to manage these challenges. Since Microsoft Updates are sourced from trusted Microsoft servers, allowing this traffic to bypass the proxy can help reduce the load on the proxy server without compromising network security. This ensures that essential updates are delivered efficiently while preserving proxy resources for other security and content filtering tasks. It is important, however, to implement such bypass configurations carefully to maintain overall network security and compliance with organizational policies.
If you are considering avoiding proxying Microsoft Updates traffic, there are two main approaches:
To bypass Microsoft Updates traffic in networks equipped with SWA, the approach varies depending on your proxy deployment setup:
| Deployment type |
Bypass traffic |
| Transparent deployment |
You can redirect Microsoft Updates traffic at the router or Layer 4 switches that are responsible for forwarding traffic to the proxy server. |
| You can configure bypass settings directly within the SWA graphical user interface (GUI). |
|
| Explicit deployment |
To prevent the Microsoft Updates traffic from reaching the SWA, you must configure the bypass at the source. This means exempting the relevant URLs on the client machines to ensure that the traffic is not redirected to the SWA. |
If bypassing specific traffic requires extensive network redesign and is not feasible, an alternative approach is to configure the SWA to pass through certain types of traffic. This can be achieved by setting the SWA to neither decrypt nor scan the designated traffic, allowing it to pass through the proxy without inspection. This method ensures that essential traffic is delivered efficiently while minimizing the impact on network performance and proxy resources.
There are four main stages to configure passthrough for Microsoft Update traffic:
| Stage |
Steps |
| 1. Create a Custom URL Category for Microsoft Updates URLs |
Step 1. From GUI, Choose Web Security Manager and then click Custom and External URL Categories. Step 5. From List Order, choose the first category to position on top. Step 6. From Category Type drop-down list, choose Local Custom Category. Step 7. Add Microsoft Updates URLs in the Sites Section.
Tip: You can check the list of Microsoft updates from: Step 2 - Configure WSUS | Microsoft Learn
Caution: Do not Copy/Paste the URLs as are in the Microsoft Documents; format them properly as SWA format. For more information, please visit: Configure Custom URL Categories in Secure Web Appliance - Cisco Step 8. Submit. |
| 2. Create an Identification Profile to exempt Microsoft Updates traffic from Authentication |
Step 9. From GUI, Choose Web Security Manager and then click Identification Profiles. Step 15. In the User Identification Method section, choose Exempt from authentication/ identification. Step 16. In the Define Members by Subnet, If you would like to Passthrough Microsoft traffic for some specific users, enter the IP addresses or Subnets that applies, or else leave this field blank to include all IP address. Step 17. From Advanced section, choose Custom URL Categories. Step 18. Add the Custom URL Category that was created for Microsoft updates. Step 19. Click Done. Step 20. Submit. |
| 3. Create a Decryption Policy To Passthrough Microsoft Updates Traffic |
Step 21. From GUI, Choose Web Security Manager and then click Decryption Policy. Step 22. Click Add Policy to add a Decryption Policy. Step 23. Use the Enable Policy check box to enable this policy. Step 27. From the Identification Profiles and Users, choose the Identification Profile that you created in the previous steps. Step 28. Submit. Step 29. In the Decryption Policies page, under URL Filtering, click on the link associated with this new Decryption Policy. Step 30. Select Passthrough as the action for Microsoft Updates URL category. Step 31. Submit. |
| 4. Create an Access Policy to Allow Microsoft Updates Traffic |
Step 32. From GUI, Choose Web Security Manager and then click Access Policy. Step 33. Click Add Policy to add an Access Policy. Step 34. Use the Enable Policy check box to enable this policy. Step 38. From the Identification Profiles and Users, choose the Identification Profile that you created in the previous steps. Step 39. Submit. Step 40. On the Access Policies page, under URL Filtering, click on the link associated with this new Access Policy Step 41. Select Allow as the action for the Custom URL category created for the Microsoft Updates. Step 42. Submit. Step 43. Commit the changes. |
| Revision | Publish Date | Comments |
|---|---|---|
3.0 |
20-Oct-2026
|
Modernization. |
2.0 |
14-Feb-2025
|
Formatting, updates. |
1.0 |
11-Oct-2024
|
Initial Release |