Bug ID 1285969: Some aggregation interface names can cause ethernet interfaces in LACP aggregations to be erroneously down

Last Modified: Jul 13, 2024

Affected Product(s):
F5OS Velos(all modules)

Known Affected Versions:
F5OS-A 1.3.2

Fixed In:
F5OS-C 1.6.0, F5OS-A 1.5.0

Opened: Apr 07, 2023

Severity: 1-Blocking

Symptoms

One or more interfaces in LACP aggregations may be considered down when they should not be.

Impact

Traffic through the affected ethernet interface in LACP aggregations may be disrupted. This can cause either degraded performance or traffic failure for LACP aggregations that the interface is a member of.

Conditions

Internally, LACPD hashes interfaces to an integer, and some aggregation interface names hash will collide with ethernet interface name hash. Changes to the these aggregation interfaces can impact the ethernet interface.

Workaround

Only use aggregation interface names that don't hash to the same port numbers as ethernet interfaces. In order to determine if an existing aggregation interfaces port number conflicts with an ethernet interface, review the lacpd_interface_stat table. For a VELOS partition, use the lacpd container on any blade in the partition to run tmctl. For an appliance, use system_lacpd container to run tmctl. The following example from a rSeries appliance shows the aggregation interface "vlag" with the same port number as interface 1.0 [root@appliance-1 ~]# docker exec -it system_lacpd bash [root@appliance-1 partition]# tmctl lacpd_interface_stat -s name,port_num name port_num ---- -------- 1.0 1024 10.0 10240 2.0 2048 3.0 3072 4.0 4096 5.0 5120 6.0 6144 7.0 7168 8.0 8192 9.0 9216 mgmt 43008 vlag 1024 If an aggregation interface hashes to the same port number an Ethernet interface: 1. Delete the conflicting aggregation interface 2a. You can either restart the lacpd containers or 2b. Reboot the appliance, or for VELOS reboot each blade in the partition.

Fix Information

Aggregation interface names will never impact ethernet interfaces in a LACP aggregation.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips