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This button will update the OS information for a node based on the file OS_Rules.nmis, located in the installation configuration directory by default. This rules are based, mostly, in the sysDescr configuration attribute. For this to be set, the community string must be correct and the device should had been successfull polled from NMIS at least, once. We can check this attribute - among others - in the node information, by clicking in the node name.
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