The Discovery Ignore List is a feature that allows you to specify the IP addresses or hostnames of the devices that you do not want to monitor or discover in the future. You can add devices to the ignore list manually or automatically during the discovery process. Once a device is added to the ignore list, it will be skipped by any subsequent discovery. You can also remove devices from the ignore list if you change your mind and want to monitor them later. Reference: Add devices to the Discovery Ignore List in NPM, Remove devices from the Discovery Ignore List in NPM, How to View Devices on Your Windows Network and What to Do If You Can't See Them

SNMP (Simple Network Management Protocol) is a protocol that allows network managers to monitor and control network devices using a set of standardized messages and data structures. SNMP uses a client-server model, where the network manager (client) sends requests to the network device (server) and receives responses. The network device has an SNMP agent that collects and reports the data using a MIB (Management Information Base), which is a hierarchical database of variables that describe the device's status and configuration. Each variable in the MIB has a unique identifier called an OID (Object Identifier), which is a dot-separated sequence of numbers that follows a tree structure12.
To retrieve a single value in SNMP, you can use two types of requests: GET and GET NEXT. A GET request asks for the value of a specific OID, and the SNMP agent responds with the value if it exists, or an error if it does not. A GET NEXT request asks for the value of the next OID in the MIB tree, and the SNMP agent responds with the value and the OID of the next variable, or an error if there is no next variable. A GET NEXT request can be useful for discovering the OIDs and values of a device, or for iterating over a table of values34.
A GET VALUE request is not a valid SNMP request, and a GET TABLE request is not a single request, but a series of GET NEXT requests that retrieve all the values in a table . Reference: 1: SNMP Basics, 2: SNMP Tutorial Part 1 - Understanding MIBs and OIDs, 3: SNMP Tutorial Part 2 - SNMP Get, GetNext, GetBulk, 4: SNMP Commands, : SNMP Table Operations, : SNMP Table Retrieval

To add a new subnet of 500 devices for monitoring, the first step is to perform a network discovery using the Network Sonar Wizard in NPM. This wizard allows you to scan your network by IP address range, subnet, or seed device and automatically discover and add nodes and interfaces to NPM for monitoring. You can also specify credentials, polling settings, and custom properties for the discovered devices. Performing a network discovery can help you quickly and efficiently incorporate new devices into NPM without manually adding them one by one. Reference: Discover your network devices, Specify subnets, Discover devices by subnets

The Export to Excel button is only displayed if the report contains only custom table resources. Other resources cannot be converted to the Excel format. https://documentation.solarwinds.com/en/success_center/orionplatform/content/core-exporting-reports-sw1547.htm#:~:text=the%20Excel%20format.-,Click%20Reports%20%3E%20All%20Reports%20in%20the%20menu%20bar%2C%20and%20click,Click%20either%20Export%20as%20Excel.

SNMP traps are unsolicited messages sent by network devices to report events or issues. If NPM receives too many traps from devices that are not managed by NPM, or traps that are not relevant for monitoring, the performance of the Orion Web Console can be affected. To resolve this issue, you can point the devices to a trap manager, such as Kiwi Syslog Server, and configure it to filter out unwanted traps before forwarding the remaining ones to the Orion Platform. This way, NPM will only process the traps that are important for monitoring and alerting, and reduce the load on the database and web server. Reference: Configure SNMP traps in NPM, Filter traps in Kiwi Syslog Server, [Forward traps to another host in Kiwi Syslog Server]