Bug ID 685344: Monitor 'min 1 of' not working as expected with FQDN nodes/members

Last Modified: Sep 13, 2023

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

Known Affected Versions:
12.1.2, 12.1.3,,, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Fixed In:

Opened: Sep 25, 2017

Severity: 3-Major


A pool with a monitor configured as 'min 1 of {...}' may be unavailable when one or more members configured with FQDN are down, rather than remain available as long as at least one pool member remains up.


The pool may be seen as 'offline' when one or more members are down, rather than remaining available as long as a single pool member is 'UP'.


-- Pool nodes/members are configured with FQDN. -- At least one associated monitor is defined with the 'min 1 of {...}' feature.


To configure a pool with 'min 1 of{...}', specify static pool members, do not use FQDN to configure pool members.

Fix Information

A pool with FQDN configured nodes/members and specified with a monitor of 'min 1 of {...}' remains available as long as a single pool member remains up. This issue is resolved by the FQDNv2 feature re-implementation.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips