xgs360028fMRSTPInstanceConfigurationHelloTime 1.3.6.1.4.1.890.1.5.8.78.2.11.1.1.2.1.5

The interval between periodic transmissions of STP Configuration Messages by Designated Ports when the Bridge Instance is the Root Bridge. range : 1 - 10 (seconds), and (HelloTime+1)*2 must be <= MaxAge. default: 2.