Switch Port Mapper - Knowledge Base

1. Switch Port Mapper does not show any MAC Addresses.

One possible reason could be that the switch does not return the MAC Addresses. Ensure that the switch is configured to return the values from the dot1dTpFdbTable of the Bridge MIB implemented in the switch. If you are not sure about this configuration, check with the Switch vendor. For example, in Extreme Summit switches, the command to enable this is: Enable snmp dot1dTpFdbTable

If problem persists, contact with the Support File.

Questions

2. Switch Port Mapper displays only the MAC Address and not the IP Address.

The possible reasons could be:

1. The Router input is not specified. Enter the Router name to resolve the MAC Addresses to IP Addresses. The Router should be in the same subnet as that of the devices connected to the switch.
2. Alternatively, you can add all your routers, gateway servers, etc., in the Admin --> Add Router settings and schedule scanning. This will periodically scan the devices to get the MAC-IP data of the devices in the network and stores them in the database. This data will be used by the Switch Port Mapper in resolving the IP Addresses of the connected devices.

Questions

3. I did a 'Switch Port Mapping' using the Switch Port Mapper tools in OpUtils. In the results, I can see several devices connected to a single switch port? How is this possible?

One possible reason could be that the device connected to that port is a Switch/Hub. In that case, the Switch Port Managemenet tool will show the devices that are connected to that Switch/Hub.

Questions

4. I imported several switches from a CSV file. I get a message that scanning failed for xx switches. What should I do?

This means that scanning of some of the switches imported from a csv file have failed. Click the link to view the details of the switches with its error details. Fix the errors by modifying the switch inputs and save. This will re-scan the switches to get the mapping details.

Questions

5. I have different router for each VLAN. How can I add them to the Switch Port Mapper tool ?

Routers specified in the Switch Port Mapper tool are used to resolve the IP Addresses of the connected devices. You can add all your routers in the Admin --> Add Router and schedule scanning. This will collect the MAC-IP data and updates the database. This data will be used by the Switch Port Mapper tool to resolve the IP Addresses of the connected devices.

Questions

6. Switch Port Mapper do not show all the ports of the switch?

One possible reason could be that we could not get the matching ports for all the ports of the switch from the Bridge MIB. The MAC Address of the devices connected to the switch port can only be resolved, if a matching port is found in the Bridge MIB. Selecting the "Show all the Interfaces" option from Switch Port Mapper settings will list all the ports of the switch, but the MAC Address will be resolved only for the ports that have an matching entry in the Bridge MIB.

One possibility that the MAC Address is not returned from the Bridge MIB could be because of the Switch Aging Time. Switches learns the MAC Addresses of the devices based on the data flowing through it. If there is not data flowing from a particular device, it will lose the data. This could be the reason for the MAC Address not being shown for a port that is UP. You can enhance the MAC resolution by using the SNMP Sweep option available in OpUtils.

1. Click the Modify icon available under the Actions column pertainig to the switch.
2. Under the Scanning Details, select the "Do SNMP Sweep Before Scanning the Switch" and add the all the possible subnets that could be connected to this switch.
   
   Note: For example, if you have a 48 port switch and the devices connected to this switch has IP Addresses from subnets 192.168.110.0, 192.168.111.0, 192.168.112.0. You can include only these subnets for a ping sweep prior to scanning this switch. If devices connected to some other switch also has IPs from these subnets, you can add them for that switch as well, but if you are sure that no devices connected to a switch will have IPs from these subnets, you do not have to add them.
3. Click Modify
4. OpUtils will perform a SNMP Sweep to these subnets prior to scanning. This will ensure that the switch learns the MAC Address of all these devices.

Questions

To create a support file for Switch Port Mapper, contact our support team.