Your wiki user page is the wrong place to ask questions. Please post to one of the Mailing lists with your questions.
Can I do blow mentioned stuff using OpenNMS??
1) simple monitoring and restart if the device is down
2) level 2, some debugging to identify the fault and escalate to the call center for dispatching to the respective vendor
3) On Cisco routers and switches also propose level 2&3 if you have the right resources