Bug ID 683697: SASP monitor may use the same UID for multiple HA device group members

Last Modified: Sep 13, 2023

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

Known Affected Versions:
12.1.2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 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

Fixed In:
14.0.0, 13.1.1.4, 12.1.3.4

Opened: Sep 15, 2017

Severity: 3-Major

Related Article: K00647240

Symptoms

Under rare timing conditions, the SASP monitor running on one member of an HA group (failover device group) may use the same LB UID as another member of the device group. The LB UID used to connect to the Server/Application State Protocol (SASP) Group Workload Manager (GWM) is required to be unique for each client connecting to the GWM. As a result, only the first HA group member using the duplicated UID is able to successfully use the SASP monitor. The SASP monitor instance running on the HA group member using the duplicated UID will fail to connect to the SASP GWM.

Impact

The SASP monitor is unable to monitor pool member availability on all members of the HA group.

Conditions

This occurs under rare timing conditions when using the SASP monitor on a BIG-IP system that belongs to an HA group. It is possible that the necessary timing conditions may occur if the external SASP monitor daemon is forcibly restarted (such as for troubleshooting purposes).

Workaround

Forcing the mcpd process to reload the configuration (as described in article K13030: Forcing the mcpd process to reload the BIG-IP configuration (https://support.f5.com/csp/article/K13030) allows recovery from this condition. It is possible that less-intrusive measures such as restarting the external SASP monitor daemon (such as by sending a SIGTERM to the SASPD_monitor process) may also allow recovery. Due to the rare occurrence of this symptom, this solution has not been confirmed.

Fix Information

The SASP monitor reliably uses a unique UID across HA group members, allowing all HA group members to successfully connect to the SASP GWM.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips