Bug ID 2224985: VIPRION (4?blade) – Per?blade cluster desync causes peer to be marked as disconnected ? HA mirroring channels

Last Modified: Feb 24, 2026

Affected Product(s):
BIG-IP Install/Upgrade, LTM(all modules)

Known Affected Versions:
17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1, 17.5.0, 17.5.1, 17.5.1.2, 17.5.1.3, 17.5.1.4

Opened: Feb 17, 2026

Severity: 3-Major

Symptoms

- In a 4-blade VIPRION chassis (part of a multi-chassis device group with multiple traffic groups), one blade intermittently reports a peer chassis as `disconnected` for traffic-group-1/2 while other blades correctly show the peer as `active/standby`. - On the affected blade, `tmsh show /sys ha-mirror` shows `Primary: connected` / `Secondary: closed` (or `closed/closed`) for all TMMs; no L4/L7 mirrored packets or contexts observed. - Chassis backplane heartbeat/peer stats are healthy (no backplane fault). - Restarting clusterd/sod/mcpd (or rebooting the blade) restores correct cluster view and mirroring.

Impact

- Connection/persistence mirroring does not occur from the affected blade. - During failover moments involving that blade's traffic, established sessions may drop.

Conditions

- VIPRION system with 4 blades installed. - Multi-chassis device group with at least 2 active traffic groups. - After upgrade to 17.5.1.x (17.5.1.4 specifically) and/or after blade role changes. - Intermittent;

Workaround

- Restart cluster stack on the affected blade: `bigstart restart clusterd sod mcpd` - Or reboot the blade; mirroring then establishes normally until condition reappears.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips