BugZero | F5 BugID 494070 - BIG-IP DNS cannot use a loopback address with fall...

F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

Last updated on July 18th, 2026

BugZero Risk Score
6.0 Medium

Overall: 6.0

Severity: 6.4

Community: 4.2

Lifecycle: 8.3

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Bug Details

Priority: 4-Minor
Status: Verified
Impact Category: Global Traffic Manager

Description

Symptoms

BIG-IP DNS cannot use a loopback address with fallback IP load balancing.

Impact

Cannot configure a loopback address using fallback IP load balancing.

Conditions

BIG-IP DNS pool using fallback IP load balancing.

Workaround

None.

Fix Information

Now, a BIG-IP DNS Pool fallback IP address can be localhost.

Change history

Links

Original Vendor Announcement

Relevant Products

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Affected versions:11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8

Fixed versions: 12.0.0, 11.6.1, 11.5.4

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.0.0, 11.6.1, 11.5.4

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F5 Integration

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F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

Last updated on July 18th, 2026

BugZero Risk Score6.0 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

F5 - Defect ID: 494070

BIG-IP DNS cannot use a loopback address with fallback IP load balancing

Last updated on July 18th, 2026

BugZero Risk Score6.0 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.0 Medium

BugZero Risk Score
6.0 Medium