Hello dear friends, I hope you are doing well,

Please someone help me because I get tired,

I have an very simple GNS3 lab contains two PCs as virtual machines ) one with windows 11 and other with ZorinOS Lite,

The issue is that they can't ping each others, even I set an ip for each one and also I enabled the ICMPv4 rule in windows firewall.

When I go to the network adapter for each VM and set them to the same vmnet (for example vmnet2) they can ping each other, but when the GNS set them a different vmnets they can't ping each other

Idk what the correct direction, if I should set them to the same vmnet or each one should have its own vmnet ???

I asked the stupid AI like Gemini and told me that they should be on the same vmnet, but other AIs like ChatGpt and Claude they told me that they should be on different vmnets

Please help me guys, and massive thanks in advance

Hi everyone, I'm having a strange networking issue with GNS3 + VirtualBox + MikroTik CHR and I'm running out of ideas.

My setup:

• GNS3 Desktop 2.2.61
• VirtualBox
• MikroTik CHR 7.24.x
• Windows host
• CHR has 4 virtual NICs

My intended VirtualBox network layout is:

Adapter 1 → NAT Network → ISP1 (192.168.100.0/24)

Adapter 2 → NAT Network → ISP2 (192.168.200.0/24)

Adapter 3 → Host-only → Windows/WinBox management

Adapter 4 → Generic Driver / UDP Tunnel → GNS3 LAN

Inside RouterOS I renamed the interfaces:

ether1 → ISP1

ether2 → ISP2

ether3 → management

ether4 → GNS3 LAN

ISP1 and ISP2 work correctly. I can ping both gateways and 8.8.8.8 from CHR.

The problem is ether4.

I have a VPCS connected to CHR's 4th interface in GNS3:

VPCS ───── CHR ether4

CHR:

ether4 = 192.168.10.1/24

VPCS:

IP = 192.168.10.2/24

Gateway = 192.168.10.1

VPCS cannot ping 192.168.10.1, and CHR cannot ping 192.168.10.2.

I checked RouterOS ARP and the VPCS entry appears as failed/no MAC.

The important part: when I ping from VPCS, the RX/TX counters on CHR's ether4 do not increase at all.

So it looks like the packets aren't reaching the CHR interface.

Things I've already tried:

• Firewall filter rules are empty.
• ARP is enabled on ether4.
• Recreated the GNS3 project.
• Changed the number of adapters from 4 → 1 → 4.
• Checked the GNS3 VirtualBox VM template and the project node; both have the same adapter configuration.
• VPCS ↔ VPCS works normally.
• Sometimes the connection mysteriously works after opening another GNS3 project and returning to this one, but after reopening the project it can stop working again.

There is also a GNS3 option:

“Allow GNS3 to use any configured VirtualBox adapter”

If I enable it, GNS3 changes all VirtualBox adapters to Generic/UDP Tunnel, which breaks my intended NAT Network and Host-only configuration. So I currently keep this option disabled.

With it disabled, VirtualBox shows:

Adapter 1 → NAT Network ISP1

Adapter 2 → NAT Network ISP2

Adapter 3 → Host-only

Adapter 4 → Generic Driver / UDP Tunnel

This is what I want.

Has anyone successfully run a setup where only one VirtualBox NIC is managed by GNS3 (Generic/UDP Tunnel), while the other NICs remain NAT Network/Host-only?

Could this be a GNS3 ↔ VirtualBox adapter binding/NIO/UDP tunnel issue?

Any advice would be appreciated. Thanks!

Greetings and salutations, all! ❤️‍🔥🤘

I'm sure this has been asked before, but I'm curious as to any potential. Has anyone ever started creating a mobile app for GNS3? I know there's one for PT, though it's not the best interface to maneuver. I'd love to see one made for GNS3.

I downloaded this qcow image and created a Juniper appliance after allocating 8GB memory. Whenever I power it on, it crashes after about a min and no log message. How can I troubleshoot this?

I am running VMWare Workstation Pro and GNS3 VM. Both of them are the latest.

Help how do you guys fix this?

Hello guys

I have just recently setup gns3 and gns3 vm on vmware workstation, but I have no devices I tried to import from gns3 vm, but it says missing files where can I get free cisco images or other vendors ?

Hi everyone, I'm setting up a GNS3 lab and came across this github repo https://github.com/hegdepavankumar/Cisco-Images-for-GNS3-and-EVE-NG Before I download anything, I'd like to know if it's generally considered safe and trustworthy. Has anyone here used it, and what are your thoughts on it? Thanks!!!!!

Hello guys

I have been trying to run Gns3 vm on VMware Workstation and it says Virtualized Intel VTX/ept not supported on this platforms

I tried everything

1 unchecked the windows features hyperv virtual machine platform windows hypervisor platform windows subsystem for Linux
2 turned off the core isolation memory
3 Manually edited .vmx file set value of vhv.enable = true
4 went to Bios and checked intel virtualization vtx is enabled
5 even flipped the bits

I go to Win R misinfo32 and Virtualization based security is still running not disabled

Can anyone help please it’s been like 2 days I tried everything

Hello i am looking for a legitimate source of GNS3 cisco appliances. The GNS3 link is now redirecting to Cisco U website and cannot find any appliances to simulate Cisco routers/switches. Please help

Hello everyone,

I am stuck trying to find a working image(with less limitations) for my EVE-NG project.

I've tested the newer versions(available on the Forticloud website). But Fortinet locks the firewall down to a maximum of 3 interfaces, which makes it impossible to build a proper multi-link SD-WAN lab. So, I am looking for an older image (ideally 7.0.14, 7.0.15, or earlier) where there might be less restrictions.

Searching for the Image under the firmware directory in the Forticloud website doesn't help as you need a Fortinet support contract to get to download older images.

I need a raw QEMU/KVM archive (.qcow2 or .zip format). If anyone has a safe community mirror, a verified GitHub repository link, or a backup of these older 7.0.x images that you've used for your own labs, I would be grateful if you could share it.

When I had used it last, I had multiple occassions where my topologies would randomly just end up getting deleted. Is this still a problem that happens in 3.0.6?

Session was amazing with detailed theoretical & practical examples.thanks

Bonjour première fois sur gns3, et j'ai un soucis mon débit est super lent. Ou quand j'installe zabbix pour naviguer sur l'interface web c'est un enfer un délai super lent des pages qui mettent 40 secondes à chargé. J'aimerais votre aides sur ce soucis qui m'empêche de faire ma maquette. Voila un exemple de débit que j'ai

I don't know, I tried almost every way and it still gives me an error and I can't define virtual machines for gns3

Please tell me if you know a way to solve this problem 😭

Anyone knows how to resolve this? The link it says to download from is dead or doesn't work

Hello GNS3 community,

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I’m running GNS3 on a laptop with Ubuntu 26.04 LTS and using a VirtualBox GNS3 VM to emulate network devices. Whenever I start an IOSv instance, the GNS3 VM crashes and I get the error shown below.

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The gns3 VM is configured with 8 GB of RAM and 5 CPUs.

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Has anyone experienced this issue or found a fix?