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Any configuration changes made locally on the switch won't be synchronized with Sophos Central. We recommend making changes from the Sophos Central control panel instead.

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Cisco Discovery Protocol

Cisco Discovery Protocol (CDP) is a Cisco proprietary protocol designed to facilitate the network management of Cisco devices by discovering hardware and protocol information about neighboring devices.

Global settings

You can configure the following settings on the Global settings tab:

  • CDP state: Turn on or turn off CDP.
  • Voice VLAN advertisement: The switch advertises the voice VLAN on all ports that are CDP-enabled and are members of the voice VLAN.
  • Mandatory TLV validation: The switch discards incoming CDP packets that don't contain the mandatory TLVs.
  • Version: Select the version of CDP.
  • Hold time: This shows the time in seconds that CDP packets are held before being discarded. The available values are 10 to 255.
  • Transmission interval: The rate in seconds at which CDP advertisement updates are sent. Available values are 5 to 254.
  • Device ID format: Select the format of the device ID. The available options are MAC (MAC address) or Serial NO (serial number).
  • Notify voice VLAN mismatch: The switch generates a syslog message when the voice VLAN information in the incoming frame and local device doesn't match.
  • Notify VLAN mismatch: The switch generates a syslog message when the native VLAN information in the incoming frame and local device doesn't match.
  • Notify duplex mismatch: The switch generates a syslog message when the duplex information in the incoming frame and local device doesn't match.

Click Apply to update the settings.

Port

The Port tab lets you configure CDP individually on each port.

To turn on CDP for individual ports, select the ports you want and click Edit. You can configure the following settings:

  • CDP state: Turn CDP on or off.
  • Notify voice VLAN mismatch: The switch generates a syslog message when the voice VLAN information in the incoming frame and local device doesn't match.
  • Notify VLAN mismatch: The switch generates a syslog message when the native VLAN information in the incoming frame and local device doesn't match.
  • Notify duplex mismatch: The switch generates a syslog message when the duplex information in the incoming frame and local device doesn't match.

Click Apply to update the settings.

Local device

You can view CDP information for each port on the Local device tab. By default, the tab shows the following information:

  • Port ID: Shows the port ID.
  • CDP status: Shows if CDP is turned on.
  • Device ID: Shows the ID of the device.
  • System name: Shows the name of the device.
  • Address 1: Shows the primary IP address of the device.
  • Address 2: Shows the secondary IP address of the device.
  • Address 3: Shows tertiary IP address of the device.
  • Capabilities: Shows the device's capabilities.

You can choose additional information to show on the Local device tab. Click the ellipsis Ellipsis. and select the options you want to show. You can choose from the following information:

  • CDP version: Shows the CDP version of the device.
  • Platform: Shows the device platform.
  • Software version: Shows the software version the device is running.
  • Local VLAN: Shows the device's VLAN identifier.
  • Voice VLAN: Shows the voice VLAN configured on the device.
  • Duplex: Shows if the port is in half-duplex or full-duplex.
  • Extended trust: Shows whether or not the port is trusted.
  • CoS for untrusted ports: The Class of Service (CoS) value that's given to all packets if the port is untrusted.
  • Power consumption: The amount of power consumed in watts.
  • Power request ID: The power request ID.
  • Power management ID: The power management ID of the port.
  • Available power: The available power in watts.

Remote device

You can view CDP information of discovered devices on the Remote device tab. By default, the tab shows the following information:

  • Device ID: Shows the ID of the device.
  • System name: Shows the name of the device.
  • CDP version: Shows the CDP version of the device.
  • Time to live: Shows the time to live.
  • Local interface: Shows the device's local interface ID.
  • Addresses: The IP addresses assigned to the device.
  • Duplex: Shows if the port is in half-duplex or full-duplex.

You can choose additional information to show on the Remote device tab. Click the ellipsis Ellipsis. and select the information you want to show from the following options:

  • Neighbor interfaces: Shows the CDP neighbor interfaces.
  • Capabilities: Shows the device's capabilities.
  • Platform: Shows the device platform.
  • Software version: Shows the software version the device is running.
  • Local VLAN: Shows the device's VLAN identifier.
  • Voice VLAN: Shows the voice VLAN configured on the device.
  • Extended trust: Shows whether or not the port is trusted.
  • CoS for untrusted ports: Shows the Class of Service (CoS) value given to all packets if the port is untrusted.
  • Management address: Shows the management address of the device.
  • Power consumption: Shows the amount of power consumed in watts.
  • Power request ID: Shows the power request ID.
  • Power management ID: Shows the port's power management ID.
  • Available power: Shows the available power in watts.

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