Bug ID 701889: Setting log.ivs.level or log-config filter level to informational causes crash

Last Modified: Jul 12, 2023

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

Known Affected Versions:

Fixed In:

Opened: Jan 15, 2018

Severity: 2-Critical


Certain log messages for internal virtual server (IVS) at 'informational' log level, cause TMM to crash when they are logged. The messages are logged at the end of an HTTP transaction to or from an IVS.


TMM crashes and restarts, causing loss of connections.


Information level logging enabled: - sys db log.ivs.level informational or - log-config filter level set to info A transaction that passes HTTP to/from an internal virtual server.


Avoid setting log.ivs.level to 'informational' or higher level and/ log-config filter level to 'info' or higher. By default the level is 'error' which does not trigger the bug.

Fix Information

Informational messages for internal virtual server (IVS) are logged as expected and TMM does not crash.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips