Can OpenStack Run Over a VXLAN Fabric Without an Overlay Controller?

At the OpenStack Summit in Hong Kong at the end of 2013, I gave a talk (video, slides) on the requirements, tradeoffs, and potential designs for deploying OpenStack over a VXLAN fabric. It’s been long enough that it feels like it’s time to revisit the topic. More specifically, I want to focus on the question of whether you can now build such a fabric with a mix of both hardware and software networking elements while only running standalone Neutron, which wasn’t really possible back when I originally gave the talk. Using an external overlay controller was considered the only way to...
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Adding Interface DHCP Support with an Event Handler

While EOS does not support DHCP on interfaces natively from the CLI, it is easy to leverage the underlying Linux operating system along with event-handlers to add this support yourself! dhclient is available natively within EOS. The trick is that you need to first get dhclient to run for a given interface you want to DHCP an address for, and then you need to take the result from dhclient and apply that to the CLI as if it were a static configured IP address. The following script (installed at /mnt/flash/dhcpintf) can be run out of an interface event-handler to start/stop...
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vEOS – Running EOS in a VM

Overview EOS is released as a single image that supports all of our platforms. That same single image can even be run in a virtual machine! This article describes how to set up a virtual machine in order to test EOS functionality, or to develop and test your own extensions. EOS in a VM EOS run in a VM can be used to test almost all aspects of EOS, including: Management Tools – CLI, Snmp, Aaa, ZTP L1 Connectivity – Link up/down (when connected to another EOS VM port), LLDP L2 – VLANs, Port-channels, MLAG L3 – Routed ports, Static routing, BGP, OSPF, VARP,...
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