Bug ID 671447: ZebOS 7 Byte SystemID in IS-IS Restart TLV may cause adjacencies to not form

Last Modified: Aug 19, 2026

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

Known Affected Versions:
11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 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, 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, 13.0.0, 13.0.0 hf1, 13.0.0 hf2, 13.0.0 hf3, 13.0.1

Fixed In:
14.0.0, 13.1.0, 12.1.4, 11.6.3.2

Opened: Jun 28, 2017

Severity: 3-Major

Symptoms

When using a BIG-IP system configured in an IS-IS network; adjacencies may fail to form with other vendor devices.

Impact

IS-IS adjacencies may not form.

Conditions

- BIG-IP configured to participate as a peer in a IS-IS network. - IS-IS peers perform strict validation on the length of the Restart TLV. -- The SystemID used by the BIG-IP system is of length 7 instead of 6. (ZebOS uses a 7-Byte SystemID.)

Workaround

None.

Fix Information

The BIG-IP system now uses a correct SystemID length in the Restart TLV.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips