Discovery Mechanism
To discover a network, NetworkView follows these steps, depending on which options you set in the Discovery options:
- Ping each address in the with the ICMP protocol. If the "Ping Required" option is checked and Ping is unsuccessful, try the next address.
- Try to find the DNS or NetBIOS name for the IP address
- Try to analyze the standard ports (FTP, TELNET, SMTP, HTTP, POP3) and the three other ports that you defined (TCP protocol only, not UDP). The information is analyzed, and if relevant, it is included in the record.
- If a port is active and NetworkView is not able to get a meaningful string, the word "OK" indicates it was active during the discovery.
- When one of these 8 ports is active, the node is automatically classified as a Server.
- Try to read the MAC address of the node in the local ARP table. If available, get the manufacturer's name and the associated type using the 6 first digits of the address. Assign the node type found in the OUI database.
- Try to open the TCP ports specified in the port scan string.
- Try to get SNMP information with one of the community names
- If SNMP is installed on the remote device, it will get the device sysObjectID, and compare it to:
- the internal hard coded devices list, then
- the external devices database (enterprises.dat).
- If it find the exact OID, the device is fully described. For example, finding a .1.3.6.1.4.1.311.1.1.3.1.1 will resolve to a Windows NT Workstation.
- the internal hard coded enterprises list, then
- the external enterprises database (enterprises.dat).
- In this case, you just know which enterprise has created the appliance. You can then verify with the sysDescription the exact device type, and add it to the external database.
- If a type was assigned by the MAC OUI database, it is replaced by the new more meaningful SNMP type.
A NetBIOS query is sent to the node. No specific rights are requested for this.
- WMI tries the accounts you have created in the WMI Credentials.
- If the domain or computer name matches one of the list, it is used first
- The current user credentials are used then
- All other accounts in the list are used.
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