# Mapping of ports and MAC addresses does not work for Cisco switches configured with SNMP v3

## Problem

In Switch Port Mapper, we rely on the SNMP protocol to retrieve port and MAC address details. However, when Cisco switches are configured with SNMP v3, it's important to note that we may encounter limitations in obtaining port and MAC address information through standard SNMP queries. This limitation arises from the fact that SNMP v3 in Cisco switches does not support these queries unless the `vlan-match` prefix command is enabled for the SNMP server.

## Solution

If Cisco switches are added using SNMP v3 credentials and the MAC address details are not displayed in the Switch Port Mapper, please follow the steps below to resolve the issue.

Execute the following command to modify the [Cisco switch configuration](https://community.cisco.com/t5/network-management/vlan-bridge-mib-and-snmpv3-contexts/td-p/1589698):

```
snmp-server group 'yourgroupname' v3 'priv' context vlan- match prefix read 'viewname'
```

(This command line creates multiple context names for all its VLAN IDs.)

1. `'yourgroupname'` should be the name of the group that has been created for SNMP v3 users.
2. `'auth'` or `'priv'` should be used based on the security level that has been configured.  
   (If the user has enabled **Authentication Method**, it should be `'auth'`, and if the user has enabled **Encryption Method**, it should be `'priv'`.)
3. If `'viewname'` has been created, it can be added; otherwise, it is not necessary.
4. Please make sure that the configuration is saved after executing the command.
5. After saving the configuration, go to Switch Port Mapper and scan the switches to resolve the issue.

## Solution for build below 128000

After executing the previously mentioned command (used for modifying the Cisco switch configuration), please proceed with the following steps:

1. Create a new file `CiscoSwitches.properties` under the `OpManager/conf` directory.
2. Add an entry into the `CiscoSwitches.properties` file like:

   ```
   switch name=vlan
   ```

   Example:

   ```
   192.161.44.100=vlan
   ```

   Replace with the appropriate switch name that is under question.
3. Stop the OpManager service.
4. Rename the `logs` folder located under the `OpManager/` directory and create a new folder named `logs` under the `OpManager/` directory.
5. Start the OpManager service.
6. Go to Switch Port Mapper and scan the switches to resolve the issue.

## More Information

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