Looking to virtualize ios for learning

I am looking to get in to Cisco networking, and I would like to virtualize Cisco ios.

Could anyone recommend any free software or website where I can start learning routers and switches?

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OctalDump

Is this the kind of thing you are looking for?

There's quite a few of these kinds of things, usually just called network simulators. For starting the most popular is Packet Tracer. GNS3 is also very popular choice. Paid for options also include NetSim from Boson, which has the advantage of coming with many labs configurations already set up for practicing towards the actual exam objectives.

A step up is Cisco's VIRL.

Some people will set up a home lab with switches, routers and cabling. Often you can buy complete kits for this. It is close to cost neutral, as you can sell it on for about the same price once you have your certification.

You can also buy time in labs, if you want to get hands on with very expensive/complex set ups. For some circumstances, this is the only reasonable choice. INE and IPExpert are two providers in this space. Including labs "in the cloud".

Online there is Free Cisco Catalyst Switch Lab

There's probably a heap more options available.

theodoxa

If you already have a server that can run a hypervisor, such as --

VMware ESXi
Linux KVM on RHEL or Ubuntu (3.10S or higher)
Hyper-V on Windows Server 2012 R2 (3.12S or higher)

you could also try Cisco's CSR-1000V. It is an Intel x86 based Virtual Router running IOS XE, which is basically a modular version of IOS that runs on a Linux Kernel. Most Versions up to 3.15.0S, which is roughly the equivalent of IOS 15.5(2)S can be downloaded without SmartNet. This is what many CCIE candidates use because of the high cost of physical routers which can run an IOS new enough for certain CCIE level topics (eigrp upgrade-cli, SHA Based Routing Protocol Authentication, etc...)

Cisco CSR 1000V Series Cloud Services Router Software Configuration Guide - Cisco CSR 1000V Series Cloud Services Router Overview [Cisco Cloud Services Router 1000V Series] - Cisco

You could also run other VMs such as a Domain Controller, DNS Server, TFTP Server, Client PC, etc...

GNS3 -- Requires Less Memory, Can Run on Most PCs, Only Emulates Older Routers (1700, 2600, 2600XM, 7200) Highly Unstable with Large Topologies (Based on Personal Experience on Multiple PCs with Suggested GNS3 Settings).

Packet Tracer -- Requires Very Little Memory, Can Run on Most Windows PCs, Simulates Newer Equipment, Limited Command Set and Sometimes Stuff Just Doesn't Work the Way it Should

CSR-1000V -- Should Have a Dedicated Server, Requires Large Amounts of Memory (This can be reduced significantly by finding the correct Transparent Page Sharing settings), Supports the latest and greatest IOSes, No Serial WAN Support, VMware Licensing can be a PITA, VMware is finicky about what Hardware it supports out of the box, Very Stable

OctalDump

Is CSR-1000V free? If so where can you download for free? I found a link a little while ago, but had to sign into Cisco.com account, and then add a support contract details.

theodoxa

OctalDump wrote: »

Is CSR-1000V free? If so where can you download for free? I found a link a little while ago, but had to sign into Cisco.com account, and then add a support contract details.

All versions used to be free, but more recently Cisco has been requiring SmartNet for some releases (mainly the new ones). You can still download most of the older versions (which are plenty new enough) without a contract.

3.17 = IOS 15.6(1)S -- Requires SmartNet
3.16 = IOS 15.5(3)S -- Requires SmartNet
3.15 = IOS 15.5(2)S -- 3.15.0S Only
3.14 = IOS 15.5(1)S -- All Releases
3.13 = IOS 15.4(3)S -- OVA for All Releases Except 3.13.4S
3.12 = IOS 15.4(2)S -- 3.12.0S Only
3.11 = IOS 15.4(1)S -- All Releases
3.10 - IOS 15.3(3)S -- 3.10.2S, 3.10.3S, and 3.10.4S, 3.10.5S (OVA or BIN)

Versions 3.14 and above (and versions 3.09 and below) require 4 GB of RAM to be allocated to each router. Versions 3.10 to 3.13 allow 2.5 GB per router. With Transparent Page Sharing (A VMware ESXi Feature), each router in my lab is using about 1 GB of RAM (with 2.5 GB Allocated). When first booted or reloaded, they will use the full 2.5 GB each, but the memory usage will drop (If TPS is properly configured). I use the "configure replace" command to avoid reloads as much as possible.

https://software.cisco.com/download/release.html?mdfid=284364978&softwareid=282046477&release=3.15.0SS&relind=AVAILABLE&rellifecycle=ED&reltype=latest

OctalDump

Thanks, this could be pretty awesome!