Configuring discovery settings

TCP ports to use for initial scan

Enter the TCP ports that will be scanned on a first scan. Use this setting to prevent scanning of any ports that you want to avoid.
The default is to use ports 21, 22, 23, 80, 135, 443, 513, 902, 3940, 5988 and 5989.
See the notes about Order of operations and TCP and UDP ports to use for initial scan.
Older versions included port 514, which can now be removed from upgraded systems.

UDP ports to use for initial scan

Enter the UDP ports that will be scanned on a first scan. Use this setting to prevent scanning of any ports that you want to avoid. The default is port 161.
See the notes about Order of operations and TCP and UDP ports to use for initial scan.

SSH ports

The default is port 22. Enter any custom ports to scan in a comma-separated list in the Change To column.

RLogin ports

Only the default port 513 is supported so must be empty or 513.

Windows ports

Only the default port 135 is supported so must be empty or 135.

Telnet ports

The default is port 23. Enter any custom ports to scan in a comma-separated list in the Change To column.

FTP ports

The default is port 21. Enter any custom ports to scan in a comma-separated list in the Change To column.

SNMP ports

The default is port 161. Enter any custom ports to scan in a comma-separated list in the Change To column.

HTTP ports

The default is port 80. Enter any custom ports to scan in a comma-separated list in the Change To column.

HTTPS ports

The default is port 443. Enter any custom ports to scan in a comma-separated list in the Change To column.

VMware Authentication Daemon ports

Only the default port 902 is supported so must be empty or 902.

Mainframe z/OS Agent ports

The default is port 3940. Enter any custom ports to scan in a comma-separated list in the Change To column.

WBEM HTTP ports

The default is port 5988. Enter any custom ports to scan in a comma-separated list in the Change To column.

WBEM HTTPS ports

The default is port 5989. Enter any custom ports to scan in a comma-separated list in the Change To column.

Valid Port States

When nmap runs port scans, it returns a result of open, closed, or filtered. Using the check boxes, you can choose which states are valid to investigate further.
• open|filtered—Discover a device that should be accessible but is not. It might be open or filtered.
• filtered—This port is open, but you still cannot connect to it. It must be filtered.
A port for which a result of open is returned is always considered valid.

Check port 135 before using Windows access methods

On Windows computers, port 135 is usually open. Selecting Yes for this option means that nmap checks whether port 135 is open before a Windows proxy is used to discover an IP device. The default is open.
In firewalled environments where a ping might be filtered by a firewall but the Windows proxy might be able to connect to the target (for example, it is part of the same Workgroup), select No.

Use last login method

Discovery uses the discovery method recorded as having been used successfully for an IP address.

Use SNMP SysDescr to identify OS

Discovery attempts to query the host's SNMP service for the SysDescr value to determine the OS.

Always try "public" SNMP community when using SNMP to identify OS

Discovery attempts to use the public SNMP community to query the host's SNMP service if no credential is available for that host. In this case, only device classification is possible.

Use Mainframe z/OS Agent to identify mainframes

Discovery attempts to connect to the z/OS Agent to determine whether the discovery target is a mainframe computer.

Use Telnet banner to identify OS

Discovery makes a Telnet connection to a host and uses the Telnet "welcome" banner to determine host and OS information.

Use HTTP(S) HEAD request to identify OS

Discovery attempts to connect to port 80 or 443 of the host and perform an HTTP or HTTPS HEAD request to determine the host and OS.

Use FTP banner to identify OS

Discovery starts an FTP session with the host and use the FTP "welcome" banner to determine host and OS information.

Use vSphere API to identify OS

Discovery makes a TCP connection to examine the header and ensure that the VMware authentication daemon is really on port 902 (or the specified port). When confirmed, Discovery makes a webservices request. This type of request requires an open VMware authentication daemon and HTTPS port, and a valid vSphere credential.

Use WBEM queries to identify Storage devices

Discovery attempts WBEM queries to determine whether the discovery target is a storage device.

Use Web API queries to identify devices

Discovery attempts Web API queries to try and determine the type of device.

Use REST API queries to identify devices

Discovery attempts WBEM queries to try and determine the type of device.

Use IP Fingerprinting to identify OS

This option controls whether discovery will use IP fingerprinting to determine the OS, if previous methods have been unsuccessful. You can configure the network ports scanned during this phase of discovery. The process of IP fingerprinting can cause instability in some legacy systems, and might trigger intrusion detection systems. This option is enabled by default.

Use open ports to identify OS

This option controls whether open ports are used to identify the OS.

Session line delay

A delay of 10 ms is introduced between each line sent by Discovery. This avoids problems where remote shells are unable to cope with rapid command sequences. Select one of the following from the list: 1, 2, 5, 10 (the default), 15, 20, 25, 50, 100 milliseconds.

Session login timeout

The length of time for the discovery script to wait for a login prompt. If the timeout is exceeded, the attempt is abandoned.
• Use the default timeout.
• 10, 20, 30, 60, 90, 120, or 180 seconds.

Maximum search window size

The amount of data to examine when detecting the shell command prompt. The default value is 512 bytes.

Warning: Changing the default value may cause significant degradation of appliance performance. Do not change this value unless directed by Customer Support.

Authorised prompt

Certain systems require an authorization step after login. At the command line, you are prompted to enter session details. The required response is usually a user name and some other information.
In the Authorised Prompt field, enter the text of the prompt.

Authorised response

Where an Authorised Prompt has been entered, you must enter the expected response (that you would enter at the command line) in the Authorised Response field.

Allowable IP Ranges

Enter the IP ranges that the appliance is permitted to scan.

You should set the Allowable IP Ranges, Excluded IP Ranges, and Scope settings as a group to ensure that the appliance only scans the required IP addresses, and where appropriate applies a scope to the IP addresses. See Overlapping-IP-addresses for more information.

Excluded IP Ranges

Enter the IP ranges that the appliance is not permitted to scan.

You should set the Allowable IP Ranges, Excluded IP Ranges, and Scope settings as a group to ensure that the appliance only scans the required IP addresses, and where appropriate applies a scope to the IP addresses. See Overlapping-IP-addresses for more information.

Scope

If this option is disabled, then all hosts are discovered, but discovery of empty IP address ranges will be slower. The default is to allow discovery to ping the host first.
If you enable this option, Discovery pings hosts before it starts a scan. Discovery will scan more quickly on empty IP address ranges, although hosts might be missed if there are firewalls configured to reject pings. In this situation, specify IP address ranges behind firewalls that you do not want to ping. See the Exclude ranges from ping option.
This option affects scanning only on networks other than the one on which the appliance is physically located.
If you are using ICMP filtering, set this option to No.
See the note about Order of operations.

Use TCP ACK 'ping' before scanning

Ping addresses with TCP ACK packets to determine which hosts are actually up. Use this option when scanning networks that do not permit ping packets. You can specify multiple ports in a comma-separated list.
This option is available only if the Ping hosts before scanning option is set to Yes.
• See the note about Order of operations.
If Use TCP ACK ping before scanning in your discovery settings is set to Yes, BMC Discovery might report a device that does not exist on the network, rather than dark space (NoResponse) under the following conditions:
• BMC Discovery pings an IP address for which there is no device, and
• A firewall in your environment is configured to respond for that IP address
To avoid this issue, we recommend that you either alter such firewall configurations or not enable TCP ACK ping.

Use TCP SYN 'ping' before scanning

Ping addresses with TCP SYN packets to determine which hosts are actually up. Use this option when scanning networks that do not permit ping packets. You can specify multiple ports in a comma-separated list.
This option is available only if the Ping hosts before scanning option is set to Yes.
• TCP SYN pings are likely to trigger IDS and firewall blocks, because they are often regarded as ping floods.
• See the note about Order of operations.
If Use TCP SYN ping before scanning in your discovery settings is set to Yes, BMC Discovery may report a device which does not exist on the network rather than dark space (NoResponse) under the following conditions:
• BMC Discovery pings an IP address where there is no device
• A firewall in your environment is configured to respond for that IP address
To avoid this issue, we recommend that you either alter such firewall configurations or not enable TCP SYN ping.

Exclude ranges from ping

Enter a list of IP addresses or IP address ranges that you do not want to ping. For example, you might want to scan IP addresses that are behind a firewall that blocks ICMP packets. If BMC Discovery pings an IP address and receives no response, it makes no further attempt to scan that IP address. Excluding a range from pinging enables you to scan IP addresses behind such firewalls.
This option affects scanning only of networks other than the one on which the appliance is physically located.

Scan retries

Number of retries to be attempted on each host. The system will retry only for machines on which the OS cannot be determined.
The Scan retries and Default OS options work together in sequence to help locate host machines.

Scan timeout

Timeout (in minutes) that applies when BMC Discovery uses nmap to determine open ports or performs OS fingerprinting. Scan timeout is not used to limit the time to scan devices. See also the credential timeout for the sessions.

Minimum time before end of window to avoid starting new scheduled discovery operations

A discovery run can take some time to complete. If it is started too close to the end of a Discovery window, it does not finish before the end of the window. To prevent this issue, you can specify a period in which discovery runs are not started. The default is 30 minutes, meaning that no discovery runs are started within 30 minutes of the end of a discovery window. Select the period from the following values in the list: 5, 10, 15, 20, 25, 30, 35, 40, and 45 minutes.

Allow scans even if no window defined

Use this option to permit or prevent discovery of desktop hosts. The default is No; that is, do not discover desktop hosts. When this option is set to No, if a Windows or Mac OS host is determined to be the desktop, the host is skipped. An SMB query is used to determine whether the endpoint is a Windows desktop. See Dark-space-scans for more information. When a host is skipped, the device_type attribute on the Device-Info-node is set to Desktop, no inferred host is created, and the corresponding DiscoveryAccess result is shown as "Skipped (Desktop host discovery has been disabled)."

Discover neighbor information when scanning network devices

Causes discovery to retrieve MAC and port information from neighboring scanned network devices. The default is Yes. Select No only if you do not want to collect any edge connectivity information.

Restore Scan Status

If enabled, scanning is enabled and you have a vault with either no passphrase or a saved passphrase the system will restart scanning when services are restarted. In all other cases restarting services will result in scanning being disabled.

Maximum concurrent requests against vCenter

The maximum number of concurrent requests that will be made against individual vCenter servers. Select the maximum number from the following values in the list: 1, 3, 5,7, 10, 15, 20 (the default), 25, and 30.

Timeout to establish a connection

The timeout for establishing a connection to the database. Select the timeout period in seconds from the following values in the list: 5, 10, 30 (the default), 60, 90, 120, and 180.

Maximum connections held open

Maximum time to hold an unused connection open

Maximum concurrent requests against vCenter

The maximum number of concurrent requests that will be made against individual vCenter servers. Select the maximum number from the following values in the list: 1, 3, 5,7, 10, 15, 20 (the default), 25, and 30.

Maximum number of AWS Systems Manager Session requests

Maximum number of concurrently active AWS Systems Manager Sessions permitted each second, for each account, for each region. AWS impose a limit on this, and if you raise the value, you might encounter dropped connections and reduced performance.

Maximum concurrently active AWS Systems Manager Sessions

Maximum number of concurrently active AWS Systems Manager Sessions, for each account, for each region. AWS impose a limit on this, and if you raise the value, you might encounter dropped connections and reduced performance.