Last Modified: Sep 13, 2023
Affected Product(s):
BIG-IP GTM
Known Affected Versions:
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 HF1, 11.5.3 HF1, 11.5.3 HF2, 11.5.4 HF1, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.4.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 12.1.0 HF1, 12.1.0 HF2, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2
Fixed In:
12.0.0, 11.6.0 HF6, 11.4.1 HF9
Opened: Mar 19, 2015 Severity: 2-Critical
As part of a larger effort to refine Virtual Server Auto Discovery and monitoring, several changes were made to improve cross version interoperability and Virtual Server matching. As part of these fixes, an error was introduced which caused some virtual servers to be deleted and rediscovered. This removed them from the Pool they were assigned to, which can cause load balancing errors.
Some virtual servers will be removed from Pools. The virtual server will be deleted and recreated, but not added back to the pool. This will result in incorrect load balancing decisions.
This can occur with Virtual Servers that were originally specified on a pre-folder aware version of BIG-IP, such as 10.2.x. When they are discovered by a folder aware version, they may be deleted from the GTM config and re-added with "/Common/" prepended to the name.
Changing the GTM config to add the virtual servers back to the pool will resolve the issue.
The discovery and monitoring of virtual servers has been made more robust to deal with cases of multiple GTM VSes pointing at the same LTM virtual, as well as naming/folderization issues.