Configuring persistent subscriptions

Persistent subscription enables the probe to use the same subscription ID when it disconnects from Nokia NSP and subsequently restarts. This helps to prevent event loss.

To configure persistent subscriptions, set the probe properties as below and manually create a persistent file $OMNIHOME/var/nokiaNSP.persistent file where the subscriptionId will be saved:

PersistentSubscription: 'true'
PersistentSubscriptionFile    : '/opt/IBM/tivoli/netcool/omnibus/var/nokiaNSP.persistent'

Warning: Nokia NSP subscriptions have an expiry time of approximately 60 minutes. If the previous subscription session has expired, the probe cannot resubscribe to the previous session. In this case, the probe creates a new subscription session and there may be event loss while the probe is down. If InitialResync is enabled, the probe resyncs from the active alarms list.

Configure $OMNIHOME/java/conf/nokiaNspKafkaTransport.properties to use nokiaNspRestMultiChannelHttpTransportPersistent.json as shown below:

httpConnectionPropertiesFile=$OMNIHOME/java/conf/nokiaNspRestMultiChannelHttpTransportPersistent.json

Configure $OMNIHOME/java/conf/nokiaNspRestMultiChannelHttpTransportPersistent.json to define the HOST and PORT as the Nokia SDN actual/virtual IP address and port number respectively.

Configure $OMNIHOME/java/conf/nokiaNspRestMultiChannelHttpTransportPersistent.json to remove DELETE_SUBSCRIPTION_ID during logout.

### REMOVE the DELETE_SUBSCRIPTION_ID block during LOGOUT
"LOGOUT":
   {    
        "REVOKE_ACCESS_TOKEN":
        {
            "uri":"https://HOST:PORT/rest-gateway/rest/api/v1/auth/revocation",
            "method":"POST",
            "headers":"Authorization=Basic ++Username++:++Password++,Accept=application/json,Content-Type=application/x-www-form-urlencoded,Use-Cookie=true,User-Agent=IBM Netcool/OMNIBus Message Bus Probe",
            "content":"token=++access_token++&token_type_hint=token",
            "contentFile": "",
            "interval":"0",
            "requireSSL":"true",
            "asEventStream" : "false"
        }
   }

Note:

If persistent subscription is enabled, if when checking the subscription, the ACTIVE stage is returned, the probe will resubscribe to the previous session using the same subscriptionId.

If the stage returned is the CREATING or RECREATING stage, the probe will disconnect. It will then retry the connection or shut down depending on how RetryCount is configured. The CREATING or RECREATING stage indicates that the Nokia NSP subscription is not yet ready.

If the stage returned is STOPPED, or the subscription ID is not found, the probe will subscribe with a new subscription session ID because the previous session has expired or cannot be found.