VLANs Test

A NetScaler appliance supports Layer 2 port and IEEE 802.1q tagged VLANs. VLAN configurations are useful when you need to restrict traffic to certain groups of stations. You can configure a network interface as a part of multiple VLANs by using IEEE 802.1q tagging. You can configure VLANs and bind them to IP subnets. The NetScaler then performs IP forwarding between these VLANs (if it is configured as the default router for the hosts on these subnets).

The NetScaler supports the following types of VLANs:

  • Port-Based VLAN: The membership of a port-based VLAN is defined by a set of network interfaces that share a common, exclusive Layer 2 broadcast domain. You can configure multiple port-based VLANs. By default, all network interfaces on the NetScaler are members of VLAN 1. If you apply 802.1q tagging to the port, the network interface belongs to a port-based VLAN. Layer 2 traffic is bridged within a port-based VLAN, and Layer 2 broadcasts are sent to all members of the VLAN if Layer 2 mode is enabled. When you add an untagged network interface as a member of a new VLAN, it is removed from its current VLAN.
  • Default VLAN: By default, the network interfaces on the NetScaler are included in a single, port-based VLAN as untagged network interfaces. This VLAN is the default VLAN. It has a VLAN ID (VID) of 1. This VLAN exists permanently. It cannot be deleted, and its VID cannot be changed. When you add a network interface to a to a different VLAN as an untagged member, the network interface is automatically removed from the default VLAN. If you unbind a network interface from its current port-based VLAN, it is added to the default VLAN again.
  • Tagged VLANs: 802.1q tagging (defined in the IEEE 802.1q standard) allows a networking device (such as the NetScaler) to add information to a frame at Layer 2 to identify the VLAN membership of the frame. Tagging allows network environments to have VLANs that span multiple devices. A device that receives the packet reads the tag and recognizes the VLAN to which the frame belongs.

By continuously tracking the traffic over the VLANs, you can quickly identify the VLAN that is handling the maximum traffic. The VLANs test does just that.

Target of the test : A NetScaler VPX/MPX

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each VLAN configured on the NetScaler appliance being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed

Host

The IP address of the host for which the test is being configured.

NetScaler Username and NetScaler Password

To monitor a NetScaler device, the eG agent should be configured with the credentials of a user with read-only privileges to the target NetScaler device. Specify the credentials of such a user in the NetScaler Username and NetScaler Password text boxes.

Confirm Password

Confirm the NetScaler Password by retyping it here.

SSL

The eG agent collects performance metrics by invoking NITRO (NetScaler Interface Through Restful interfaces and Objects) APIs on the target NetScaler device. Typically, the NITRO APIs can be invoked through the HTTP or the HTTPS mode. By default, the eG agent invokes the NITRO APIs using the HTTPS mode. This is why, the SSL flag is set to Yes by default. If the target NetScaler device is not SSL-enabled, then the NITRO APIs can be accessed through the HTTP mode only. In this case, set the SSL flag to No.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Data received

Indicates the amount of data received over this VLAN during the last measurement period.

MB

Compare the value of these measures across VLANs to identify the VLAN that is experiencing the maximum traffic.

Data transmitted

Indicates the amount of data transmitted over this VLAN during the last measurement period.

MB

Packets received

Indicates the number of packets received over this VLAN during the last measurement period.

Number

Compare the value of these measures across VLANs to identify the VLAN that is experiencing the maximum traffic.

Packets transmitted

Indicates the number of packets that were transmitted over this VLAN since the last measurement period.

Number

Broadcast packets sent and received

Indicates the total broadcast packets that were sent and received on this VLAN during the last measurement period.

Number

 

Packets dropped

Indicates the number of inbound packets that were dropped upon reception by this VLAN during the last measurement period.

Number

Ideally, the value of this measure should be zero.