Neighbor scanning in IPAM
Neighbor scanning attempts to retrieve the status of a device that is not responding to ICMP. It scans the ARP table of a neighbor router to determine what IP addresses are active.
Neighbor scanning is disabled by default, as it can increase router CPU usage, and therefore should only be enabled when needed.
- Go to My Dashboards > IP Address Management > Manage Subnets & IP Addresses.
- Select a subnet containing the device or devices that are not responding.
- Click Edit.
- Scroll to the bottom of the Edit Subnet Properties Window.
- Uncheck the Disable Neighbor Scanning checkbox.
Additional options are displayed.
- Enter the Neighbor IP Address and select a Scan Interval.
- Click Test to verify connection.
- Click Save.
How Neighbor scanning works
IPAM first checks if the device is capable of SNMP and supports an ARP table.
- To check whether SNMP is available, IPAM uses these OIDs:
OidSysContact "1.3.6.1.2.1.1.4.0" iso.org.dod.internet.mgmt.mib-2.system.sysContact.0 - To check whether the ARP table is available, it uses:
OidIPNetToMediaTable "1.3.6.1.2.1.4.22" iso.org.dod.internet.mgmt.mib-2.ip.ipNetToMediaTable
The IPNetToMediaTable is pulled for client information. If the device supports this table, then IPAM can use this information.