904 CHAPTER 57: IS-IS CONFIGURATIONLogging the AdjacencyChangesFollow these steps to configure this task:n With this feature enabled, the state information of the adjacency is displayed onthe configuration terminal.Enabling an Interface toSend Small Hello PacketsFollow these steps to enable an interface to send small hello packets (without thepadding field):Enabling IS-IS Trap Follow these steps to enable IS-IS trap:Configuring IS-IS GR An ISIS restart may cause the termination of the adjacencies between a restartingrouter and its neighbors, resulting in a transient network disconnection.IS-IS Graceful Restart can help to solve this problem by notifying its neighbors itsrestarting state to allow them to reestablish the adjacency without removing it.The IS-IS Graceful Restart provides the following features:■ When restarting ISIS, a Graceful Restart capable device will resend connectionrequests to its neighbors instead of terminating their adjacencies.■ Graceful Restart minimizes network disruption caused by LSDB synchronizationbefore LSP packets generation.■ When a router starts for the first time, it sets the overload bit in LSP packetsbefore LSDB synchronization is complete, which ensures no routing loop iscreated.To do... Use the command... RemarksEnter system view system-view --Enter IS-IS view isis [ process-id ][ vpn-instancevpn-instance-name ]--Enable to log the adjacencychangeslog-peer-change RequiredEnabled by defaultTo do... Use the command... RemarksEnter system view system-view --Enter interface view interface interface-typeinterface-number--Enable the interface to sendsmall hello packets that haveno padding fieldisis small-hello RequiredStandard hello packets aresent by default.To do... Use the command... RemarksEnter system view system-view --Enter IS-IS view isis [ process-id ][ vpn-instancevpn-instance-name ]--Enable IS-IS Trap is-snmp-traps enable RequiredEnabled by default
