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6

If I have a switch or laptop running a PPPOE server, could I go from ethernet-to-modem then connect the modem's WAN port to another modem's WAN port and have it connect via PPPOE? No. A DSL modem is the CPE part of a DSL link. You can't connect two CPEs, only CPE to COE, e.g. a DSLAM. DSLAMs usually require substantial infrastructure, so a lab environment ...


6

Assuming you don't specifically need VLANs you'd pick one port to be the master port for each group and set it to be the master port for every other port in the group. Ports with the same master port are isolated from ports with a different master port. Then you set a IP address on the master port for routing (if necessary). For example, if you assume three ...


5

ARP is a protocol to resolve a layer-3 address to a layer-2 address. If there is no layer-3 address assigned to the device, then ARP cannot help you. Apparently, the device is sending frames because the MAC address shows in your MAC address table. You can check the OUI to see the NIC manufacturer of the device. You could also try CDP and LLDP to see if the ...


4

Sorry, no. ROMMON can be told to ignore any NVRAM config, but there's no documented method to override the NVRAM startup-config. (Note: I'm aware of a US DoD contractor that does this, but they have customized hardware.) In a virtualized environment (GNS3, Cisco's virtual labs, etc.), it's easy to replace NVRAM entirely, or replace NVRAM contents. And this ...


4

Packet tracer is a simulator unlike GNS3 which is an emulator. so you cant run linux guest os in packet tracer


3

Packet tracer is fairly limited. It is designed to let someone practice for the CCNA exams. It doesn't include all the IOS features, only a subset of commands that are useful for CCNA-level exercises. Packet Tracer is not going to give you what you seem to want.


3

This is a common scenario. One way that this is done is with a firewall. You can place a firewall so that the test network/lab is on the outside of the firewall. That way, you can connect to the lab from the production network, but the lab cannot connect to the production network. Using a second NIC in your PC may also work, depending on the level of ...


2

The answer to your question, "how is this possible?" is simply the obvious: The modem is not acting in the way you would expect a network device (like a Cisco router) to function. Writing the code to route packets is harder than it looks, and many companies, especially with consumer-grade products, take shortcuts. In this case it appears that your modem ...


2

You should look into Cisco VIRL. Much more options and seems to be Cisco’s roadmap for emulation instead of packet tracer.


1

I finally managed to google a solution. https://learningnetwork.cisco.com/thread/102933 In VM Maestro -> Preferences -> Topology Editor -> uncheck the "Associate new connections with interfaces silently" check box -> Apply. It will bring up a drop down interface list when using the Connect tool.


1

You can use Open vSwitch. It has many enterprise grade features, including port mirroring. You will find on this documentation page the following information: Q: How do I configure a port as a SPAN port, that is, enable mirroring of all traffic to that port? A. The following commands configure br0 with eth0 and tap0 as trunk ports. All traffic ...


1

When you want to telnet to a Cisco device, you must have a password configured for the VTY lines. Use something like this: line vty 0 15 logging synchronous exec-timeout 15 0 password <your telnet password> login transport input telnet !


1

Catalyst SmartInstall for Zero Touch Switch Deployment SmartInstall can enable plug-and-play configuration and image management for zero-touch deployment on new and existing Cisco Catalyst LAN switches and zero-touch replacement of existing switches that need to be replaced in a return materials authorization (RMA) scenario. Nexus 5000 PowerOn ...


1

You have an ISR and a DHCP server, but you need a TFTP server, then you can just use SmartInstall for Zero Touch Switch Deployment: Abstract SmartInstall provides a suite of capabilities that help deploy new Cisco® Catalyst® switches and manage them effectively at very low operating costs. SmartInstall has true zero-touch switch installation to lower ...


1

Here is how you accomplish a virtual MT instance acting as gateway for a bunch of VMs. ESXi: Add 2 vSwitches. The first one is called "WAN" and you add the physical NIC to that switch. The second is called "LAN" and has no physical interfaces. Configure your virtual MT with 2 E1000 NICs, one connected to WAN and one to LAN. Boot the virtual MT and ...


1

The lab environment needs to be able to be torn up, torn down, erased, etc. IP connectivity is going to get messed up. That's the whole idea behind a terminal server and console ports. You might try using something like Docker?


1

You have routing turned off, so the router won't forward packets. You can enable it with Ip routing Thanks to @ronmaupin for noticing that.


1

When creating ACLs in a Cisco router, you use wildcard masks. Where you have a bit set to 0 in the wildcard mask, that bit must exactly match in the address. Remember that addresses and masks, including wildcard masks, are really just 32-bit numbers. This only works for IPv4; IPv6 uses CIDR notation. For example: ip access-list 10 deny 192.168.2.0 0.0.1....


1

I would go with VLAN at the OS level. I suppose the students don't have administrative privilege on the operating system. If so you can configure 2 virtual adapters in the operating systems, one for the desktop access to the internet and the other connected to the VM. With proper VLAN filtering the student should not be able to mess up things.


1

You don't have routes (either static or with a routing protocol) in the routers to reach the other router's loopback address. Routers should not have a default gateway (this is a rookie mistake), and the switches can't be gateways, anyway, since they are layer-2 devices. You can put in static default routes, static specific routes, or run a routing protocol ...


1

ACL placement is important, and the ACL design is dependent on whether it is inbound or outbound. The general rule for ACL placement is that extended ACLs should be placed as close to the traffic source as possible, and standard ACLs should be placed as close to the traffic destination as possible. If you think about the contents of the ACLs and how they ...


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