Bug ID 536935: Spurious link messages on unpopulated SFP interface

Last Modified: Oct 17, 2023

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

Known Affected Versions:
11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 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

Opened: Jul 31, 2015

Severity: 4-Minor

Symptoms

On BIG-IP 2000/4000 systems the driver that manages the MAC and PHY for the 2.x front panel ports will occasionally emit a pair of spurious log messages which appear to indicate that the [unpopulated] port had a link up message followed immediately by a link down message.

Impact

The impact this issue has is largely cosmetic but it can cause confusion or concern if at first glance one assumes the message is from a port that is actually in use.

Conditions

This appears to occur only intermittently, only on the 2.x ports of BIG-IP 2x00/4x00 systems, and only when the ports are enabled but are not cabled to a live link partner.

Workaround

In most cases a port left unpopulated can safely be disabled with (for port 2.1 for example): tmsh modify net interface 2.1 disabled which should prevent the system from polling the MAC's link state and logging changes.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips