Bug ID 2277817: DNS64 may fall back to QTYPE=A if there is a delay in response for QTYPE=AAAA and "DNS IPv6 to IPv4" is set to 'secondary'

Last Modified: May 05, 2026

Affected Product(s):
BIG-IP DNS(all modules)

Known Affected Versions:
17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1, 17.1.3.2, 21.0.0, 21.0.0.1

Opened: Apr 15, 2026

Severity: 3-Major

Symptoms

DNS64 may fall back to QTYPE=A if there is a delay in response for QTYPE=AAAA and "DNS IPv6 to IPv4" is set to 'secondary'.

Impact

DNS64 could fall back to QTYPE=A

Conditions

DNS profile with DNS64 "DNS IPv6 to IPv4" is set to 'secondary'. There is a delay in the response for QTYPE=AAAA

Workaround

NA

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips