Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

TMcGov_92811's avatar
TMcGov_92811
Icon for Nimbostratus rankNimbostratus
Jan 24, 2013

Disable STP on LTM4200V ver 11.2.1

  We are implementing a pair of new F5 LTMs in our environment. In our test lab we are cross connecting a 802.1q trunked interface from each cluster member to two separate Cisco switches. In th...
config
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Jessed12345's avatar
Jessed12345
Icon for Employee rankEmployee
Jan 24, 2013

BPDUGuard is why the ports are moved to blocking even though they are configured with portfast. Disabling that on the LTM ports should also stop this from occuring.

To disable STP on the LTM from the CLI using TMSH, the command is:

 tmsh> modify net stp-globals mode disabled

From the GUI it's under Network -> Spanning Tree -> Options

--jesse