Operation Manual – ISISH3C S9500 Series Routing Switches Chapter 1 IS-IS Configuration1-8To do... Use the command...Enable IS-IS on the specified Interface isis enable [ tag ]Cancel this designation undo isis enable [ tag ]1.2.4 Setting Priority for DIS ElectionIn the broadcast network, IS-IS needs to elect a DIS from all the routers.When you need to select a DIS from the IS-IS neighbors on the broadcast network, youshould select level-1 DIS and level-2 DIS respectively. The higher the priority is, themore possible it is selected. If there are two or more routers with the highest priority inthe broadcast network, the one with the greatest MAC address will be selected. If all theadjacent routers' priorities are 0, the one with the greatest MAC address will beselected.The DISs of Level-1 and Level-2 are elected separately. You can set different prioritiesfor DIS election at different levels.Perform the following configuration in interface view to set/restore priority for DISelection:To do... Use the command...Set the priorities for DIS election on theinterfaceisis dis-priority value [ level-1 |level-2 ]Restore the default priorities for DISelection on the interfaceundo isis dis-priority [ level-1 |level-2 ]By default, the interface priority is 64. If the level-1 or level-2 is not specified, it defaultsto setting the priority of both Level-1 and Level-2.1.2.5 Setting Router TypeBased upon the position of the router, the levels can be divided into Level-1(intra-domain router), Level-2 (inter-domain router) and Level-1-2 (that is, intra-domainrouter as well as inter-domain router).Perform the following configuration in IS-IS view to set/restore the router type:To do... Use the command...Set the router type is-level { level-1 | level-1-2 | level-2 }Restore the default router type undo is-levelBy default, the router type is level-1-2.
