Netconf and Yang

Cisco’s acquisition of Tail-f prompted me to look deeper into what Tail-f does. That in-turn made me dig deeper into Netconf and Yang. Netconf is a device configuration and management protocol and Yang is a modeling language that’s used by Netconf. Yang modeling can also be used outside Netconf’s context. From looking at the history behind Netconf and Yang, I realized that Network management as a whole was a widely ignored topic for quite sometime. The current Network management techniques used by Operators seems to be very arcane and the recent SDN wave has triggered a renewed interest in simplifying Network management. In this blog, I will cover the following:

  • Shortcomings of SNMP.
  • Netconf and Yang overview with examples.
  • Comparison with Ovsdb and Openflow.
  • Opendaylight’s use of Yang model
  • Tail-f  NCS system’s use of Netconf and Yang.

Continue reading Netconf and Yang →

Cloud policy – Congress and Opflex

Recently, I saw a lot of press on Cisco’s Opflex protocol that allows a declarative policy model to control a physical or virtual device. There were discussions around if the Opflex protocol would replace Ovsdb and Openflow. Within Openstack, there is a new project called Congress that allows for creating a policy framework within Openstack. This blog is my attempt to get into more details on Congress and Opflex and explain the relationship between them. This is mostly information gathered from different references that I have listed in the end.

Congress:

Congress is a new Openstack project that is used to enforce compliance within the cloud environment. The end goal would be to integrate Congress with other cloud orchestration software as well. Compliance could be needed because of Government regulations, contracts between organizations, SLA enforcement etc. Following picture illustrates the need for Congress.

Continue reading Cloud policy – Congress and Opflex →

White box switches – Overview and current models

In this blog, I will cover the basics of White box switches, current software models in White box switches, architecture overview of popular White box vendors(Cumulus, Big Switch, Pica8), popular Opensource projects related to White box switches and some final thoughts on the future direction.

In the current Networking switches, hardware and software are tightly coupled and it is not possible to change the software from 1 vendor to another keeping the hardware as same. This is different from Server space where hardware and software are decoupled completely.

The term White box Switch refers to a Networking Switch where hardware and software are loosely coupled and it is possible to change 1 of them keeping the other as same.

Following are some of the advantages of White box switches.

  • Multiple choices and no vertical lock-in to a single vendor.
  • Can increase speed of innovation.
  • Can reduce capex and opex.

Following are 3 models that seems to be emerging among White box switches.

Continue reading White box switches – Overview and current models →

Openstack Networking Demo

This blog covers a hands-on session demonstrating Openstack networking capabilities. This is a followup to my previous blog where I covered the Openstack Icehouse installation and basic usage. I have covered the following in the video.

  • Connectivity between VMs in a single subnet.
  • Connectivity between VMs across different subnets by having a router between the 2 subnets.
  • Connectivity between VMs across 2 different hosts and establish connectivity between the VMs using GRE tunnel between the 2 hosts.
  • Using Access security control policies to control access to VM.

VMs used are same as previous blog:

Controller localrc can be found here. Compute localrc can be found here. I had some issues getting connectivity across hosts working with network type vlan and vxlan. I am not clear if the issues are with the ovs switch version that I have or with the localrc configuration. Open vswitch version I am using is 1.4.6.

Continue reading Openstack Networking Demo →

Openstack Icehouse install using Devstack

In this blog, I will cover steps to install Openstack Icehouse release using Devstack. I will cover Single node installation as well as Multi-node installation. In a single node installation, both control and compute instance runs in the same VM. In multi-node install, control and compute instance runs in 1 VM/host and a compute instance runs in another separate VM/host. In multi-node install, we can spin as many compute instances as needed. With 12GB RAM in my host, I was running out of memory with single control and compute instance and a bunch of host applications running in my system.

My environment:

  • Windows 7 with Virtualbox 4.3.10
  • 12 GB RAM

Downloadable VM:

I have created OVA files for both the controller and compute instance that can be downloaded from below links. Import the OVA files into any VM manager software like Virtualbox to try this out. These VMs are running Ubuntu 12.04.

Alternate locations for downloading VMs in case the Dropbox link above does not work:

Following are the steps that I did to create the VMs above. If you are downloading the OVA files, you don’t need to follow the steps below. Continue reading Openstack Icehouse install using Devstack →

Openstack Overview

In 1 of my previous blogs, I have given overview of Cloud OS and comparison of the popular Cloud OS available in the market today. Currently, the most popular opensource cloud OS in the market is Openstack. Openstack has lot of momentum going for it along with a great industry backing.

Following blog gives a good overview of Openstack components, release history along with comparison of Openstack components with AWS.

Openstack can be downloaded from here. It is pretty complex to install Openstack since there are multiple components involved. Similar to linux distributions provided by linux vendors, there are multiple vendors offering Openstack distributions. Following blog covers popularOpenstack distribution vendors. More vendors are joining into the fray now. These distributions offer easier deployment, customizations, performance tuning as well as support. The best way to try out Openstack is using devstack. Devstack offers a scripted approach to install and try out Openstack. In 1 of the next blogs, I will cover the Openstack install procedure using Devstack.

Hybrid Cloud

In the recent Rightscale survey, 74% of the respondents mentioned that they have a multi-cloud strategy and 48% of the respondents are planning for hybrid clouds. The recent trend in Cloud computing after Public and Private cloud is Hybrid cloud. Hybrid cloud offers the best of Private and Public cloud in some scenarios and Enterprises seem to like that.

In this blog, I will cover the following:

  • What is Hybrid cloud and Multi-cloud?
  • Use cases for Hybrid cloud.
  • Components of Hybrid cloud and design considerations – Cloud management, Network connectivity, Application portability
  • Popular Hybrid cloud providers – Rightscale and AWS, Vmware VCHS, Cisco Intercloud, Rackspace hybrid cloud, Redhat open hybrid cloud

Continue reading Hybrid Cloud →

Network Virtualization – Openstack+ODL integration

In my previous blog, I covered basics of Network Virtualization and overview of commercial solutions available today. The most popular Open source Network Virtualization solution available today is Opendaylight. With the hydrogen release of ODL, ODL can be downloaded in 3 flavors: Base edition, Network Virtualization edition and Service provider edition. Network Virtualization edition adds components like Ovsdb, Opendove, VTN as well as Openstack integration. Ovsdb, Opendove and VTN are different approaches to provide multi-tenant networks. Ovsdb team has put in a nice set of hands-on tutorials for folks wanting to try out Openstack+ODL. I recently tried this out and I was very impressed. In this blog, I will cover my experiences in trying out hands-on Openstack+ODL integration.

Continue reading Network Virtualization – Openstack+ODL integration →

Network Virtualization – Overview and popular commercial solutions

In this blog, I will cover the following:

  • Overview and need for Network Virtualization
  • Relation between Cloud management and Network Virtualization
  • Network Virtualization approaches
  • Overlay Networks
  • Service chaining
  • Popular Network Virtualization solutions – Vmware NSX, Juniper Opencontrail, Cisco ACI.

Overview and need for Network Virtualization

Network Virtualization allows for abstracting the Networking resources into a logical/software model so that the same set of physical resources can be shared by multiple tenants in a secure and isolated manner. There are 2 kinds of Networking resources, one is the physical resources like Router, Switch and another is appliances like Firewall, Load balancer etc. The appliance can be either physical or virtual. NFV(Network functions virtualization) can be considered a subset of Network Virtualization.

Network Virtualization is similar to Server Virtualization. In server virtualization, compute resources are virtualized, while in network virtualization, networking resources are virtualized. Network virtualization took much longer time to come to the market compared to server virtualization. Following picture gives a good comparison between the 2.

Continue reading Network Virtualization – Overview and popular commercial solutions →