Bug ID 851581: Server-side detach may crash TMM

Last Modified: Sep 13, 2023

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

Known Affected Versions:
12.1.0, 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,,,,,,,,, 13.1.1,,,,, 13.1.3,,,,,,, 13.1.4,, 13.1.5,, 14.0.0,,,,,, 14.0.1,, 14.1.0,,,,,, 14.1.2,,,,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,

Fixed In:
16.0.0, 15.1.1,

Opened: Nov 20, 2019

Severity: 2-Critical


TMM crash with 'server drained' panic string.


TMM crash, failover, brief traffic outage. Traffic disrupted while tmm restarts.


-- Server-side flow is detached while the proxy is still buffering data for the pool member and the client continues to send data. -- The detach may be triggered by the LB::detach iRule commands or internally.


-- In cases in which the detach is triggered internally, there is no workaround. -- In cases in which the detach is triggered by LB::Detach, make sure the command is not executed when a request may still be in progress by using it in response events, for example HTTP_RESPONSE, USER_RESPONSE, etc.

Fix Information

TMM does not crash no matter when the server-side detach is triggered.

Behavior Change

Guides & references

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