Bug ID 1211513: Data payload validation is added to HSB validation loopback packets

Last Modified: Jun 16, 2024

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

Known Affected Versions:
13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,,, 13.1.1,,,,, 13.1.3,,,,,,, 13.1.4,, 13.1.5,, 14.0.1,, 14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,, 15.1.6,, 15.1.7, 15.1.8,,, 15.1.9,, 16.0.0,, 16.0.1,,, 16.1.0, 16.1.1, 16.1.2,,, 16.1.3,,,,,, 17.0.0,,, 17.1.0,,,

Fixed In:
17.1.1, 16.1.4, 15.1.10

Opened: Dec 20, 2022

Severity: 3-Major


Send validation loopback packets to the HSB on the BIG-IP platforms.


No impact, this is a new diagnostic feature.


This issue occurs while running a BIG-IP hardware platform with HSB.



Fix Information

Loopback validation now occurs on hardware platforms equipped with HSB, except on iSeries platforms i4600, i4800, i2600, i2800, and i850 as wd_rx_timer is disabled by default.

Behavior Change

A new diagnostic feature with failsafe periodically sends validation loopback packets to the HSB on BIG-IP platforms with the hardware component. The feature adds following two new db variables that can be altered with TMSH modify sys db: - The variable tmm.hsb.loopbackValidation is enabled by default, change it to disabled to stop the loopback validation packets sent to HSB. - The variable tmm.hsb.loopbackvalidationErrthreshold is set to 0 by default. If this value is set to 0, the BIG-IP will only log corruption detection without taking any action. If the value is set to greater than 0, then an HSB nic_failsafe will be triggered when the number of detected corrupt loopback packets reaches the value. An HSB reset typically dumps some diagnostic information in /var/log/tmm and reboots the system. If a validation loopback packet is found to be corrupt, one or more messages like the following will appear in /var/log/tmm: notice HSB loopback corruption at offset 46. tx: 0x4f, rx: 0x50, len: 2043 These logs are rate-limited to 129 logs per 24-hour period. If the variable tmm.hsb.loopbackvalidationErrthreshold is set to a value greater than 0 and the number of corrupt packets reaches this value, the following log message will also appear: notice Reached threshold count for corrupted HSB loopback packets Typically, the log message will then be followed by a reboot.

Guides & references

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