Bug ID 597899: Disabling all pool members may not be reflected in Virtual Server status

Last Modified: Sep 23, 2022

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

Known Affected Versions:
12.1.3, 12.1.2, 12.1.1, 12.1.0, 12.0.0, 11.5.4

Fixed In:
13.0.0, 12.1.4

Opened: Jun 07, 2016

Severity: 3-Major

Related Article: K86025623

Symptoms

When all pool members are set to session-disable, the expectation is that persistent connections will be drained, and the Virtual Server should not accept new incoming connections. - Simply disabling (not forcing down) a node does not bubble up to Pool status, because it switches from Green-Enabled to Green-Disabled (staying green is seen as a non-change). - Since the Pool enabled/disabled state is not updated, this does not bubble up to the Virtual Server, which also stays Green-Enabled.

Impact

Disabling all members of a Pool may not be reflected in Virtual Server status, indicating it is Green-Enabled when in fact it has been disabled indirectly by disabling all members of the related pool.

Conditions

-- All pool members are set to session-disable. -- Persistent connections existing on the associated Virtual Server. -- New connections to associated Virtual Server. -- Viewing Virtual Server status.

Workaround

N/A

Fix Information

When all pool-members are disabled via GUI or tmsh, Virtual Server shows Green-Disabled (visually represented as gray) and is still able to process traffic from an existing connections but not able to accept newer traffic. Green-Disabled status roll-up to Pool (from Pool Member / Node Address) is still necessary. But instead of marking the Virtual Server Yellow, which would stop existing traffic flows on the Virtual Server, the BIG-IP system propagate the Green-Disabled status to the Virtual Server as well. So in the case where all the Pools associated with a Virtual Server are Green-Disabled (because all the Pool Members for all the Pools are Green-Disabled), the status of the Virtual Server will become Green-Disabled. As soon as any Pool (Pool Member) becomes Green-Enabled, the Virtual Server will also become Green-Enabled. Note: Green-Disabled shows up as gray in the GUI.

Behavior Change

When all pool members are set to session-disable, the virtual server state is set to disabled-by-parent, persistent connections will be drained, and the virtual server does not accept new incoming connections.

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips