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11

Open vSwitch has a section on that in their FAQ: Q: Why would I use Open vSwitch instead of the Linux bridge? A: Open vSwitch is specially designed to make it easier to manage VM network configuration and monitor state spread across many physical hosts in dynamic virtualized environments. Refer to Why Open vSwitch? for a more detailed description of ...


6

The IOS XRv 9000 is probably a bit of an oddball - it's IOS-XR based. I never got round to get my hands on it or any other device running IOS-XR. That's carrier and service provider grade stuff, and my CCNA/CCNP SP career never quite took off. You're probably looking for the Cisco CSR1000V, and yes, that's a perfectly "normal" IOS-XE based router in a VM ...


4

The no. of VTY lines depends on IOS version installed. Starting IOS 12.2, 16 VTY lines are allowed.


4

This is actually a known issue and there are a couple of ways to fix it. The best one is actually to edit the XML definition for the libvirt network and add trustGuestRxFilters=yes to the opening network definition stanza. The default is "no" - which, unfortunately, breaks both IPv6 and multicast for IPv4. This is actually laid out in a RedHat Bug ...


4

JFL was correct it was a NIC checksum offloading error. My guess is that when my virtual router was behind my physical router it somehow made it so it didn't need to do checksumming. Recap of Problem: Scenario A: virtual behind physical resulted in 88mbps (pfsense 2.4.2 as a KVMguest on CentOS 7 with default settings on the pfsense install.) (...


4

A logical switch is a switch function implemented in software-defined networking. This isn't necessarily connected to VXLAN tunneling. Whether a logical switch is virtual or not is a matter of perspective. A virtual switch is a (somewhat) more common L2 switch that's integrated in a hypervisor (or otherwise non-physical). VLAN is no virtual switching ...


4

What you're referring to is actually a sub-interface. A sub-interface is an interface where the name & number of the interface is dependent on another interface. So, gig0/0.30 would be a sub-interface because its number is dependent on gig0/0, which is a physical interface. Another example of a sub-interface would be serial0/0:23 because it's ...


4

A virtual interface will always go down if the corresponding physical interface goes down, it's nothing more than an interface which is used to handle traffic with a specific VLAN tag on the physical interface.


4

Under the hood, all virtualization systems, including docker, use the same mechanism: they use a software switch on the host. Such a switch can be called a "virtual switch" (but this is a bit grey since you now have hardware switches that use a linux kernel and the exact same software to run). All modern OSes have a built-in, basic, software switch that the ...


3

So the functional distinction between hardware and software is actually a lot less than you might think. Most - if not all - switching and routing functions are first specified, implemented and debugged in software implementations long before they're adapted to run on a piece of dedicated silicon. This is, of course, because the process of changing, fixing ...


3

What exactly is a virtual AP? Depends on which vendor or product you are talking about. In general, I would define a virtual AP as a "logical AP" rather than a physical AP device. This may involve providing multiple logical APs on a single physical device or treating multiple physical devices as a single logical AP. Are there multiple ways of ...


3

A quick google search turns up the doc "Supported Platforms for Unique MAC Address Configuration on VLAN or L3 Interfaces for Catalyst Switches" which learns us that both the default behaviour as well as the potential to change the MAC address, are very different depending on the switch model (and in some cases, depending on the IOS version). So, look up ...


3

There is no way to do what you want to do. VDCs virtualize control plane and data plane in protected memory so that each is an independent virtual device, just like independent physical devices. You can, of course, ask Cisco to consider adding this feature in a future NX-OS release. From Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration ...


3

I have found a way to enable my virtual router to act as router for the physical device, solving my problem. EDIT: As Teun Vink has a valid point I'll try to explain my solution. I have removed the OpenSense Virtual router from the network and connected the Cisco router directly to the vSwitch0 interface (VM network). I have put the vSwitch0 interface in ...


3

There is no specific term (that I'm aware of). A "virtual network," "virtual segment," or perhaps "layer 2 domain" all might be acceptable. You can also look at Docker or Kubernetes documentation to see how they describe it. Whatever terms they use are most likely to be the ones that are accepted.


3

You seem to be talking about https://ieeexplore.ieee.org/document/8382313. I haven't read the document, but it's mentioned in the abstract: In this paper, we propose joint optimization of scaling, placement, and routing (JASPER), a fully automated approach to jointly optimizing scaling, placement, and routing for complex network services, consisting of ...


3

If you want the academic answer, NIST has published a nice paper on what Cloud Computing is. The definition they use is: The NIST Definition of Cloud ComputingCloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and ...


2

Your premise is not necessarily true. Some Cisco routers do have VTY lines 0 to 15, and some older Cisco switches only have VTY lines 0 to 4. As far as I know, you can configure line vty 0 15 on a Cisco 1941 router. It won't show lines 5 to 15 unless you actually configure them. I don't have direct experience with the 1941, but every ISR G2 router that I ...


2

Your behaviour of slow browsing and fast file transfers is consistent with DNS problems. As you stated, you are using as DNS servers 4.4.4.4 and 8.8.8.8. It is a common mistake assuming 4.4.4.4 is a Google DNS Server (or it was in the past, not so sure). It belongs to Level 3 Communications, and it is only open for their customers. $whois 4.4.4.4 .... ...


2

Basically an Ethernet switch does the following. 1. Use the source MAC address of the frame to update it's MAC address table. 2. Look up the destination MAC address of the frame in it's MAC address table. 3a. If there is a match in the table and the egress port is different from the ingress port forward the frame. 3b. If there is a match in the table and ...


2

Instead of looking up a MAC in the central unit and sending it to a dedicated unit, what if I would just put any incoming packet on our bus as local broadcasts, and let the slave units do the MAC matching? What you're describing is functionally equivalent to an Ethernet hub


2

In a nutshell, an Ethernet switch forwards frames based on their destination MAC address. For that it learns source addresses and associated ports. It also drops damaged frames that fail FCS. For this basic functionality, switches don't exchange information on their own, they just forward frames. Each one does its job independently. Managed switches usually ...


2

The Virtual Circuit Identifier (VCI) is used for reliably transferring packets by L2/L3 virtual circuits and allows higher level protocols to avoid dealing with the division of data into segments, packets, or frames. The VCI is added by the intermediate routers/switches running protocols such as X.25, Frame Relay, Asynchronous Transfer Mode (ATM), GPRS, ...


2

Yes, many vendors of networking equipment offer virtual alternatives nowadays for their physical hardware. It allows you to use the full power and featureset of a real networking device (a switch, router, firewall or load balancer for example) within virtualized environments. You can also run them on a dedicated hypervisor for more performance. Especially ...


2

As long as you have connectivity between your GNS3 and your LAN, this is going to work just fine.


2

K, it turned out that the version I was using is no longer supported! using the latest stable release I managed to achieve the L2TPv3 tunnel and pass traffic through it.


2

I'd have called that a "virtual ethernet": there are ethernet addresses, ARP packets, broadcasts. It's virtual because there is no medium. It's definitely not a VPN, as there is what that is understood to mean is a system where the private leased-lines are virtualised onto shared lines, normally generic internet. While it is clearly some kind of virtual ...


2

The client keeps sending re-transmits(5-8 of them) to to a secondary server, and it ignores them. That would be incorrect. If the failover server does not have a TCP connection with the sending host, TCP will send a RST upon receiving a segment in a non-existent connection, killing the connection on the host, which will need to establish a new connection ...


1

On the vHosts' vSwitches, you use port groups to connect VMs to a common network. These port groups can be associated with VLAN IDs for a physical network which you need to use to connect both vSwitches. Use the same VLAN ID on both hosts. On the physical switch, add the VLAN as tagged to the host ports and you're set. (Of course, the vSwitch needs to have ...


1

Of course, physical hardware is required to interface between the physical and the virtual world, but not necessarily switches. A virtual host with just a single NIC could house an entire large virtual network with its own virtual switches and routers. Virtual machines and switches are connected by logical connections (associations), not cables. Cables are ...


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