Bug ID 645674: 'bigd' message send to 'mcpd' failure is not logged

Last Modified: Apr 28, 2025

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

Known Affected Versions:
11.6.1, 11.6.1 HF1, 11.6.1 HF2, 11.6.2, 11.6.2 HF1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 12.1.5.1, 12.1.5.2, 12.1.5.3, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Fixed In:
13.1.0

Opened: Feb 16, 2017

Severity: 3-Major

Symptoms

A bigd message to mcpd notifying of monitor status change may fail to be sent, without log notification, when the message is too large.

Impact

Mcpd is not notified of the monitor status change, and the missing message is not logged. The monitor reflects an incorrect status until a future status change triggers a successful notification-message to be sent from bigd to mcpd.

Conditions

A message sent from bigd to mcpd that is too large (e.g., because of the unbounded accumulation of HTTP/1.1 200 codes with unique values).

Workaround

Diagnosis of an incorrect monitor status may identify this issue, but no direct workaround is available. The issue of the too-large bigd message is described in ID 645197, and involves the accumulation of unique HTTP/1.1 200 codes (indicating monitor success) without a monitor status-change for extended time (days or weeks). When a monitor status change finally occurs, bigd cannot notify mcpd because the message is too big. Thus, there is no indication of the monitor-status change. The secondary issue, here, is that there is no log message indicating the status-change-message-send failure.

Fix Information

When bigd attempts to send mcpd a message notifying of montor status change, and that message is too large, the issue is logged.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips