H3C MSR 20-20 Command Reference Manual page 651

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Use the command to disable the security
undo voice vlan security enable
mode for voice VLAN.
By default, the security mode of voice VLAN is enabled.
n
The voice vlan security enable and undo voice vlan security enable
commands take effect only after the voice VLAN attribute is enabled globally.
Example # Disable the security mode of the voice VLAN.
<Sysname> system-view
[Sysname] undo voice vlan security enable