Posts Tagged ‘vlan’

Dell VRF-lite & VMware NSX: Multitenancy Across Physical & Logical Networks

Saturday, December 20th, 2014

Please checkout the white paper Dell Networking: Multitenancy Across Physical and Logical Environments with VRF-lite and VMware NSX. In the white paper I discuss use cases and how NVO and VRF-lite can be used together to deploy a consistent multitenant framework across logical and physical networks. In this short blog, I expand on the concept I presented in a prior blog, Multitenancy on Dell Networking Switches via VRF-lite, of how NVO and VRF-lite together can be used to deploy a consistent multitenant framework across logical and physical networks. (more…)


Dell Networking and VMware NSX: Bridging Between Logical & Physical Networks

Wednesday, November 5th, 2014

In a prior blog, Creating Logical Networks and Services with VMware NSX on Dell Infrastructure, I discussed how easily VMs can be moved from physical (VLANs) to logical networks (Network Virtualization Overlays or NVOs). In practicality, there will almost always be some physical resources on a network that are not virtualized or remain on the physical network (VLANs). So how can VMs on a logical network communicate with resources on the physical network?

One method of communication can be done with the VMware NSX L3 Edge Services Router. However, if you want to just bridge between the logical and physical entities such as bridging between VXLAN to VLAN, the VMware NSX L2 Gateway can be used and this specific use case is discussed in more detail in this blog. (more…)


Creating Logical Networks and Services with VMware NSX on Dell Infrastructure

Thursday, October 16th, 2014

If you haven’t already, please checkout the Dell-VMware NSX Reference Architecture (RA) whitepaper. In the reference architecture I explain in detail the foundational NSX-vSphere components and also how Dell can provide a complete end-to-end infrastructure (servers, networking, storage) to support a robust SDN solution with NSX. In this blog, I will provide a quick overview, some insight on NSX, and examples of VMware NSX deployment with a complete end-to-end Dell infrastructure. (more…)


Automating VLAN Configuration on Dell FTOS Switches via GVRP

Saturday, February 22nd, 2014

GARP VLAN Registration Protocol (GVRP) is a standards-based protocol defined in the IEEE 802.1Q specification that provides for automatic VLAN configuration on switches. The Generic Attribute Registration Protocol (GARP) is used by switches supporting GVRP to register/de-register attribute values such as VLAN IDs between switches within the network. GVRP is the standards-based equivalent to Cisco’s Virtual Trunk Protocol (VTP). To read more about Cisco VTP, read my prior blog at For this blog, I utilize 2 x Dell S60s [FTOS ]and 1x Dell S50N [FTOS]. Below is the network diagram for this lab. (more…)


Dell Force10 Z9000 – Creating Additional Layer 2 Isolation via Private VLANs

Saturday, July 7th, 2012

Private VLANs provide additional segregation capabilities within a VLAN. A private VLAN provides further layer 2 isolation between ports. A common example of private VLAN use is a hotel providing Internet access for patrons while at the same time preventing direct access between guest ports. Instead of using private VLANs, you can create a separate VLAN and assign a separate IP subnet to each guest as shown below. (more…)


802.1Q Trunking Between Cisco and Dell Force10 Switches

Monday, July 2nd, 2012

VOIP PhonesIn this lab I use a Dell Force10 S25P switch [FTOS] and a Cisco C3750 switch [IOS 12.2(25)SEE3] to demonstrate 802.1Q trunking. (more…)


Configuring PVST+ on Cisco Switches

Wednesday, February 1st, 2012

Per VLAN Spanning Tree Plus (PVST+) is a flavor of Spanning Tree Protocol (see prior blog, Default STP Behavior on Cisco Switches) which maintains a spanning tree instance for each VLAN in the network. This means certain VLAN trunks (using 802.1q) can be forwarded for some VLANs while being blocked for others. Further, changes in one STP domain will not effect other spanning tree instances on other VLANs. Additionally, since each VLAN is treated as a separate network, layer 2 load balancing can be accomplished by forwarding some VLANs on one trunk and other VLANs on another trunk. (more…)


Cisco VLAN Trunking Protocol (VTP)

Wednesday, November 23rd, 2011

VLAN Trunking Protocol (VTP) is a Cisco proprietary protocol that reduces administration in a switched network. When you configure a new VLAN on one VTP server, the VLAN is distributed through all switches in the domain. This prevents you from having to configure the same VLAN everywhere. The goal is to manage all configured VLANs across a switched internetwork and to maintain consistency. (more…)


Cisco – Spanning VLANs across Switches via Trunking

Sunday, November 20th, 2011

In this lab I use two Cisco WS-C2960-24TT [IOS 12.2(25)FX] switches to demonstrate how to span VLANs across switches via 802.1q trunking. I avoid using VTP by using “VTP transparent mode”; as a result, I have to configure the VLANs on both switches. Also, the Cisco 2960 switch only allows you to use 802.1q encapsulation. However, on some other Cisco switches the default encapsulation is a Cisco proprietary protocol called Inter-Switch Link (ISL). If you are using one of these switches and you want to use 802.1q instead of ISL, you will have to manually change the encapsulation type. (more…)


Setup Inter-VLAN Communication via “Router on a Stick”

Wednesday, March 30th, 2011

This lab demonstrates inter-VLAN communication via the “Router on a Stick” method. To enable inter-VLAN communication, a trunk link is created between a router and switch. Trunk links can carry traffic for multiple VLANS. Trunk links can also be used to span VLANs across multiple switches and allow them to communicate with each other. In general, communication between VLANs must go through a layer 3 device. (more…)