Help Center> Anti-DDoS> FAQ> About Threshold and Black Hole> What Can I Do If an IP Address Is Blocked?
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What Can I Do If an IP Address Is Blocked?

Possible Causes

Anti-DDoS provides a 2 Gbit/s DDoS mitigation capacity for free, and its maximum mitigation capacity can reach 5 Gbit/s (depending on the available bandwidth of HUAWEI CLOUD). HUAWEI CLOUD Anti-DDoS will trigger a black hole to block access from the Internet within a time period when detecting an ECS is under volumetric flood attacks.

Solution

You can use either of the following methods to unblock the IP address:

  • The system automatically deactivates the black hole 24 hours after the IP address was blocked.

    If the system detects that the attack traffic still persists and exceeds the threshold, the IP address will be blocked again.

  • Advanced Anti-DDoS (AAD) is recommended because it automatically deactivates the black hole 30 minutes, by default, after the black hole has been triggered. The duration of persistent black hole depends on the times of the black hole triggered and volume of peak attack traffic of the day, and it can be a maximum of 24 hours. If you need to permit access before a black hole becomes ineffective, upgrade Anti-DDoS to AAD and contact Huawei technical support.
Anti-DDoS defends against most common DDoS attacks at no additional charge, whereas Advanced Anti-DDoS (AAD) provides expanded protection and expert support with subscription fees. For details, see Table 1.
Table 1 Differences between Anti-DDoS and Advanced Anti-DDoS

Item

Anti-DDoS

AAD

Charging

Free of charge

Charged

Protection capacity

Provides a 2 Gbit/s DDoS mitigation capacity, and its maximum mitigation capacity can reach 5 Gbit/s.

A maximum of 1 Tbit/s protection capacity

Protected object

HUAWEI CLOUD resources only

On- and off-premises

Protection policy
  • Fixed protection policies
  • Basic CC attack defense
  • Globally applied policies
  • Diverse protection policies
  • Professional CC attack defense
  • Customized policies

Key event assurance

None

Expert support (for VIP customers)

Detailed reports

Provides an overview report.

Provides a detailed report.

Technical support

24/7 online customer service

24/7 expert support service