Slower transfer speeds between VLANs vs same VLAN

I am using Sangfor firewall as a gateway (router) with various VLANs, but I'm experiencing notably slow data transfer speeds in the Kbps range when copying data from one VLAN to another. I seek assistance in addressing this issue.

Slow data transfer speeds between VLANs on your Sangfor firewall could be attributed to various factors. Here are some steps you can take to troubleshoot and address the issue:

1. **Check Network Configuration:**
   - Verify that the VLAN configurations on your Sangfor firewall are correct.
   - Ensure that the VLANs are properly configured on all the devices connected to the network.
   - Check for any misconfigurations in IP addresses, subnet masks, or gateway settings.

2. **Firewall Rules and Policies:**
   - Review the firewall rules and policies for inter-VLAN traffic. Make sure that the firewall is not overly restrictive, causing unnecessary delays.
   - Check if there are any specific rules limiting the bandwidth between VLANs.

3. **Hardware Resources:**
   - Inspect the hardware resources of your Sangfor firewall. Insufficient resources can lead to performance issues. Ensure that the firewall has enough processing power, memory, and bandwidth to handle the traffic.

4. **Firmware/Software Updates:**
   - Ensure that your Sangfor firewall is running the latest firmware or software updates. Manufacturers often release updates to address performance issues and improve stability.

5. **Traffic Inspection and Logging:**
   - Examine any traffic inspection or logging features enabled on the firewall. Excessive logging or deep packet inspection can impact performance. Consider adjusting these settings if they are causing a bottleneck.

6. **QoS (Quality of Service) Settings:**
   - Check if Quality of Service (QoS) settings are configured. Incorrect QoS settings can lead to prioritization issues, affecting the performance of specific types of traffic.

7. **Physical Network Inspection:**
   - Inspect the physical network infrastructure, including cables, switches, and routers. Faulty hardware or poor cable quality can lead to network issues.

8. **Bandwidth Monitoring:**
   - Implement bandwidth monitoring tools to identify the source and destination of high traffic. This can help pinpoint where the slowdown is occurring.

9. **Isolate the Issue:**
   - Try to isolate the issue by testing data transfer speeds between devices within the same VLAN and between different VLANs. This will help determine if the problem is specific to inter-VLAN communication.

10. **Contact Support:**
    - If the issue persists, consider reaching out to Sangfor support. Provide them with details about your network setup, configurations, and the specific issue you're facing. They may be able to offer further assistance or guidance.

By systematically going through these steps, you should be able to identify and address the factors contributing to slow data transfer speeds between VLANs on your Sangfor firewall.

For Android mobile users, you may encounter issues with displaying the login dashboard for a captive portal when using social media login. Here are some potential reasons and solutions for this problem:

Captive Portal Restrictions: Android devices have restrictions on displaying captive portal login pages when using certain types of authentication, including social media login. This can prevent the login dashboard from being displayed properly.

Solution 1 - Custom Authentication: Consider implementing a custom authentication system for your captive portal. This would involve creating a separate login page specifically designed for mobile devices, including Android. By using a custom authentication system, you can ensure that the login dashboard is displayed correctly on all devices.

Solution 2 - User Agent Detection: Another approach is to detect the user agent of the device accessing the captive portal. Once the user agent is identified as an Android device, you can redirect the user to a mobile-friendly version of the login dashboard that is compatible with Android.

Solution 3 - App Integration: If applicable, you may also explore the option of creating a dedicated app for your captive portal. This app could provide a seamless login experience for Android users, bypassing the need for a web-based login dashboard.

Testing and Compatibility: It's important to thoroughly test the captive portal on various Android devices to ensure compatibility and proper display of the login dashboard. Consider using different models and versions of Android devices during the testing phase to identify any potential issues.

User Experience Consideration: Regardless of the solution chosen, it's crucial to prioritize user experience. Ensure that the login process is intuitive and user-friendly for Android mobile users, as this can greatly impact the success of the captive portal implementation.

By addressing these considerations and exploring the suggested solutions, you can work towards resolving the issue of displaying the login dashboard for Android mobile users when using a captive portal with social media login.

can try check iperf from vlan to another vlan and check, also factors on protocol or port permission on the firewall need to be carefully not deny certain port that can affect transfer of data

there are several possible causes and troubleshooting steps you can try:

1. Basic troubleshooting:

    Verify cable connections: Ensure all network cables are securely plugged into the correct ports on the Sangfor firewall and other network devices. Faulty or loose cables can significantly impact data transfer speeds.
    Reboot devices: Sometimes, a simple reboot of the Sangfor firewall and other network devices can resolve temporary glitches or software issues.
    Check for errors: Look for any error messages in the Sangfor firewall logs or event viewer on other devices. These may provide clues about the source of the slow speeds.

2. Sangfor firewall configuration:

    Inter-VLAN routing: Make sure inter-VLAN routing is enabled on the Sangfor firewall for the specific VLANs experiencing slow speeds. You may need to consult the Sangfor documentation for specific configuration steps.
    QoS settings: Check if any Quality of Service (QoS) settings are applied on the Sangfor firewall that might be prioritizing other traffic over data transfers between VLANs. Adjust QoS settings if necessary to prioritize data transfers.
    Security policies: Review any security policies applied to the VLANs that might be throttling data transfer speeds. For example, if you have intrusion detection or prevention systems enabled, they might be impacting performance.

3. Network equipment:

    Check for overloaded interfaces: If the interfaces on the Sangfor firewall or other network devices are overloaded with traffic, it can lead to slowdowns. Use monitoring tools to check interface utilization and identify any bottlenecks.
    Faulty hardware: Although less likely, it's possible that faulty hardware on the Sangfor firewall or other network devices could be causing the slow speeds. If you've exhausted other troubleshooting options, consider replacing any suspected hardware.

4. Additional tips:

    Upgrade firmware: Ensure you're using the latest firmware version for the Sangfor firewall and other network devices. Outdated firmware can sometimes cause performance issues.
    Contact Sangfor support: If you've tried all of the above troubleshooting steps and are still experiencing slow speeds, contact Sangfor support for further assistance. They may be able to provide more specific guidance based on your network configuration and logs.

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Hi, you have to check your networking devices in order to troubleshooting this issues about intra vlan traffic. I suggest you that if you have two vlans that do a lot of traffic to each other, you can use a layer 3 switch in order to set it as a gateway on these two vlans to avoid uneccessary traffic data to go to sangfor firewall. Layer 3 Switch are made to manage a lot of traffic between vlans.

If these VLANs are part of your LAN segment then check Policies > Access Control in the application control policy. If there is only allows connection from LAN to WAN, then create a separate allow policy from LAN to LAN.

Slower transfer speeds between VLANs compared to transfers within the same VLAN can be attributed to several factors within the network infrastructure. Ensure that the Sangfor firewall's routing capabilities are optimized for inter-VLAN traffic by confirming that its configuration allows efficient routing and isn’t bottlenecked by excessive rules or limitations. Additionally, inspect the network switches to guarantee they support sufficient throughput for inter-VLAN traffic and have proper VLAN configurations without any misconfigurations or bottlenecks at the port level. Investigate potential congestion points, ensuring there are no bandwidth constraints, and consider segregating heavy traffic devices or applications onto different VLANs to alleviate network congestion. Conducting thorough tests, examining the firewall settings, checking switch configurations, and potentially redistributing network loads can help resolve the slow transfer speeds between VLANs.

HiHi,

Are you trying to ping VLANs to each other?  Is it unable to ping a PC on a different VLAN?

If yes, please follow the link below to create a LAN-to-LAN allow policy:

https://knowledgebase.sangfor.com/detailPage?articleData=%7B%22articleType%22%3A1,%22articleId%22%3A%2282aef540c86b41b58d3017013000472f%22,%22keyword%22%3A%22%22%7D