Use this procedure to configure an IST MLT.
For SMLT to function properly, you must manually disable STP on all SMLT, IST, and SLT ports in all spanning tree groups or instances to which the ports belong. From Release 6.2 onwards, STP is automatically disabled by software on all SMLT ports. You must also disable STP on all edge switch MLT ports that are connected to the SMLT or SLT.
In the row containing the desired MLT, double-click the PortMembers field.
Select the ports to include in the MLT and click OK.
For the 5000 Series, up to eight same-type ports can belong to a single MLT.
Double-click the MltType field and choose istMLT from the list.
Select any field in the IST MLT row and click the istMlt button.