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When ARP cache refresh is enabled for a LAN switch, before further collection of switch-forwarding data, NetMRI pings all known the IP addresses that are known to exist as members of the device's switch-forwarding table, by relating previously gathered switch-forwarding data MAC addresses to determine their IP addresses. Since this requires a prior SPM poll, the first poll of any switch by SPM after the device is added to the license will not perform an ARP cache refresh.
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The appliance also tracks the time period required to collect switch-forwarding data and compare compares the result to the last ARP refresh. Once a timeout period is exceeded, NetMRI will re-perform the refresh on the switch, and repeat as necessary as data is collected from the device.
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