Bug ID 719597: HA between VIPRION chassis with B2250 blades might not work when running v12.1.1 and v13.1.0

Last Modified: Sep 13, 2023

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

Known Affected Versions:
12.1.1, 12.1.2, 12.1.3,,,,,,,, 12.1.4,, 12.1.5,,,, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,, 14.0.0,,

Fixed In:

Opened: May 10, 2018

Severity: 2-Critical


When two VIPRION chassis with B2250 blades try to form a high availability (HA) connection, with one running v12.1.1 and the other running v13.1.0, HA connections between TMMs on Active and TMMs on Standby might fail.


Fail to form HA connection.


-- Two VIPRION chassis with B2250 blades. -- One blade running v12.1.1 and the other running v13.1.0. -- Try to configure HA connection.


There is no workaround other than installing the same software on both blades.

Fix Information

A new sys db mhdag.bitshift is added to support HA configurations using B2250 blades running v12.1.1 and v13.1.x. Set mhdag.bitshift to 5 on VIPRION chassis with B2250 blades running v13.1.x by running the following command: tmsh modify sys db mhdag.bitshift value 5 HA between VIPRION chassis running v12.1.1 and v13.1.x with B2250 blades now works as expected.

Behavior Change

Guides & references

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