Bug ID 822245: Large number of in-TMM monitors results in some monitors being marked down or delay in marking node down

Last Modified: Oct 17, 2023

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

Known Affected Versions:
13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 13.1.3.5, 13.1.3.6, 13.1.4, 13.1.4.1, 13.1.5, 13.1.5.1, 14.0.1, 14.0.1.1, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 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, 14.1.3.1, 14.1.4, 14.1.4.1, 14.1.4.2, 14.1.4.3, 15.0.0, 15.0.1, 15.0.1.1, 15.0.1.2, 15.0.1.3, 15.0.1.4, 15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2

Fixed In:
16.1.0, 15.1.4, 14.1.4.4

Opened: Sep 05, 2019

Severity: 4-Minor

Symptoms

- When configured with a large number of in-TMM monitors, Nodes are marked DOWN when they are actually UP. - When configured with a large number of in-TMM monitors, Nodes or Pool Members may not be marked DOWN immediately after the configured timeout period once the target stops responding to pings. - When using the in-TMM monitoring feature, monitored targets (Nodes/Pool Members) may be marked DOWN unexpectedly if there is a delay in responding to ping attempts. Specifically, if the ping response from the target is delayed by more than the interval value configured for the monitor, but less than the timeout value configured for the monitor, then the target may be marked DOWN.

Impact

- Monitor target may appear DOWN when it is actually UP. - Nodes or Pool Members which are not responsive may not be marked DOWN in stipulated time. - The monitored target may be marked DOWN if it does not respond to ping attempts within the interval value configured for the monitor, instead of within the timeout value configured for the monitor.

Conditions

This may occur when the one of the following conditions are met: - The in-TMM monitoring feature is enabled (through sys db bigd.tmm). - A large number of Nodes and/or Pool Members (several hundreds or thousands) are configured and monitored. - Monitored target does not respond to ping attempts within the interval value configured for the monitor.

Workaround

Disable in-TMM monitors: tmsh modify sys db bigd.tmm value disable

Fix Information

N/A

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips