Last Modified: Sep 13, 2023
Affected Product(s):
BIG-IP DNS, GTM
Known Affected Versions:
14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 16.0.0, 16.0.0.1
Fixed In:
16.1.0, 16.0.1, 15.1.1, 14.1.3.1, 13.1.3.5
Opened: Jun 19, 2020 Severity: 2-Critical
GTM/DNS monitors based on the TCP protocol may fail to find the configured receive string in the server's response, causing the monitored service to be incorrectly marked down.
A service is incorrectly marked down. This can cause the BIG-IP GTM/DNS to return a suboptimal answer or no answer at all to DNS queries.
This issue occurs when the server's response spans multiple packets (for example, when the response is particularly large or includes dynamically generated content delivered in chunks).
This issue can be worked around by ensuring your server returns a response to the BIG-IP GTM/DNS's monitor that fits in one packet.
GTM/DNS monitors based on the TCP protocol no longer fail when the server's response spans multiple packets.