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Showing posts from December, 2015

SDN Wars: Cisco ACI vs VMware NSX

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In the last few years, with an exponential growth of interest in the SDDC (Software Defined Data Center), many vendors have shown an interest, and some have even managed to engineer a more-or-less decent SDN (Software Defined Networking) solution. Some are an experienced Networking Hardware vendors, while the others are Startups trying to to enter the big markets using this new tendency. Cisco ACI and VMware NSX are the top two SDN solutions according to Gartner, and according to various other entities (Network World, SDxCentral etc.).

If you have doubts regarding the concept of SDN, or a difference between SDN and Network Virtualization, check out my previous posts [Check out the Blog Map]:

Network Virtualization vs SDNShould I go for CCIE or learn SDN?Is SDN really the future?

Why do I consider myself to be the "right" person to analyse and compare these 2 SDN Solutions? Because I've worked a lot with both technologies, and I can be objective because:

I've worked a l…

Cisco ACI: AVS and Hypervisor Integration

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At this point I will assume that you already read my previous posts about:
Cisco ACI Fundamentals.
Application Network Profiles, Contracts and Outside World connection.

If you did, then great. We may proceed with the "cool" stuff, such as ACI Virtual Switch and Hypervisor Integration.


AVS (Application Virtual Switch)

AVS (Application Virtual Switch) is the ACI version of Nexus 1000v or a Cisco alternative to a VMware vSphere VDS (Virtual Distributed Switch). If you are not familiar with these - these are virtual Switches, and they "live" on the Hypervisor, such as VMware ESXi (vSwitch), Hyper-V or KVM.




AVS also has VEM (Virtual Ethernet Modules) like the OVS (you may read about the OVS in my OVS introduction for Network Engineers), but instead of the VSM (Virtual Supervisor Module) it has the APIC Controller. It can be used instead of the VDS in the vSphere, or any other Compatible Hypervisor. It uses VLAN or VXLAN encapsulation, so - a pretty standard setup.

What is …

Cisco ACI: Application Network Profiles, Contracts and ACI Connection to the Outside Network

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By know you should know the following facts about ACI:

Cisco Nexus 9k Switches make the ACI Fabric, which is the Control and the Data plane of ACI Architecture.The main components of the ACI Architecture are Bridge Domain (BD), EPG (End Point Group) and the Private Network.VXLAN is the encapsulation mechanism that enables ACI remote L2 connectivity.

If you have any doubts about any of the "facts" on the list, you should read my previous post about the ACI Fundamentals: Components.

N9k can run in one of the two Operational Modes:
-NX-OS Mode (by default)
-ACI Mode

There are 3 types of chips in the 9k devices. You should be very careful when buying these switches because depending on the N9k models you buy, you might get only one or two of the possible ASIC chipsets:

T2 ASIC by Broadcom is a default chipset as a Nexus in a standalone mode (NX-OS mode) ALE – APIC Leaf Engine (ALE performs ACI leaf node functions when the Nexus 9500 switch is deployed as a leaf node in an ACI infr…

Cisco ACI Fundamentals: ACI Components

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Before we get deeper into the ACI (Application Centric Infrastructure) as the Cisco's official SDN solution, we need to clarify a few terms that will be used:

SDN is a concept that introduces the Networks that are configured and defined using the Software. You can read more about the SDN and Network Virtualization in one of my previous posts.APIC (Application Policy Infrastructure Controller) is the SDN controller that Cisco ACI architecture uses as the Management Plane.Spine and Leaf is also known as the ACI Fabric. This architecture was explained in my VMware NSX introduction here. In the ACI world Spine and Leaf are the Cisco Nexus 9000 Series Switches (N9k) in the ACI mode, and they are the Control and the Data plane of the ACI.VXLAN (Virtual eXtensible LAN) is the encapsulation technology on which all the SDN solutions are based, because it permits users on different subnets, even on remote routed networks, to see each other as if they were on the same L2 Segment. Read more ab…

Can OpenStack Neutron really control the Physical Network?

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This is a question I´ve been hearing a lot when we present the OpenStack to a new client, mostly from the guys who control the Networking infrastructure. So, can the OpenStack Neutron module really control and configure the Physical Network? The answer might disappoint you. It depends! One thing is for sure - there is no better way to make a group people put on the Poker Faces, then to try to explain how OpenStack Neutron works to a Networking Operations team.

There are 3 of us doing the technical part of the OpenStack presentation:

OpenStack Architect. Typically this will be a young fella, enthusiastic about stuff, and the impression that he gives away is that he is completely ignoring how Data Center is traditionally defined, and his answer to almost all of the questions is - "OpenStack will control that too!"Virtualization Engineer. Seen as openminded by the traditional Mainframe experts, and completely ignored by the OpenStack guy.Network Engineer (me, in our case). Seen …