i can't install gns3

i can’t do te gns3 installation. Please help me

└──╼ #sudo apt-get install gns3
Reading package lists… Done
Building dependency tree
Reading state information… Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
libqt5core5a : Breaks: libqtcore4 (< 4:4.8.7+dfsg-20~) but 4:4.8.6+git64-g5dc8b2b+dfsg-3+deb8u1 is to be installed
Breaks: libqtcore4:i386 (< 4:4.8.7+dfsg-20~) but 4:4.8.6+git64-g5dc8b2b+dfsg-3+deb8u1 is to be installed
qdbus:i386 : Depends: qtchooser:i386
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
└──╼ #

sudo apt install python3-pip
sudo pip3 install gns3-gui gns3-server

If I may, installing using Python’s pip3 works and gets the interface up, but it does not install other dependencies like ubridge, qemu, vpcs, Dynamips, etc. (BTW: GNS3 is in the Parrot repo, but is not installable.)

With the other dependencies installed, GNS3 still lacks ubridge which is not a Python package, nor is it available in the Parrot repository. So while the interface opens up and it seems to be running, trying to link 2 routers together causes the following output, even after rebooting:

GNS3 management console.
Running GNS3 version 2.2.17 on Linux (64-bit) with Python 3.9.1 Qt 5.15.2 and PyQt 5.15.2.
Copyright © 2006-2021 GNS3 Technologies.
Use Help -> GNS3 Doctor to detect common issues.

=> Error while creating link: uBridge is not available, path doesn’t exist, or you just installed GNS3 and need to restart your user session to refresh user permissions.

I’m trying to get things working using modified/updated commands from the GNS3 Linux Install page and the official PPA but am running into errors. This is what I’m trying so far:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F88F6D313016330404F710FC9A2FD067A2E3EF7B

echo “deb http://ppa.launchpad.net/gns3/ppa/ubuntu focal main” | sudo tee /etc/apt/sources.list.d/gns3.list

sudo apt-get update
sudo apt-get install -y gns3-gui gns3-server

Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
The following NEW packages will be installed:
gns3-gui gns3-server ubridge

But then running gns3 has issues with

File "/usr/bin/gns3", line 6, in <module>
    from pkg_resources import load_entry_point

I got my Cisco CCNA last year and used GNS3 a lot using the provided virtual machines and on various Linux distros directly. I’ll continue to try to resolve.

Must be very old version from Debian side

It should be installed easily from apt.

We can package gns3 packages and use auto update server for it but it is not now. We are doing the source code maintaining automatically. “We” here means only me and it is going to be > 100 packages and our traditional new year (my country) is next month so well don’t expect anything.

I understand: you have many other things to attend to. I’ll continue to work on resolving how to install GNS3, if it’s possible with Parrot’s rolling Debian branch. And hopefully other users interested in running GNS3 on Parrot can assist.

I only see ubrich is not on repository -> Can’t use cloud. Other packages like qemu, vpcs, dynamips are on repo and install it just fine. gns3 on VM is having the libvirt error -> Can’t use NAT

Yeah, I had all the other dependencies installed via Parrot repositories.

I changed the GNS3 Ubuntu release from Focal to Groovy and it complained that the libc was older than required, besides the “from pkg_resources import load_entry_point” error.

echo “deb http://ppa.launchpad.net/gns3/ppa/ubuntu groovy main” | sudo tee /etc/apt/sources.list.d/gns3.list

So now I booted up Parrot 4.11 Beta 2 and switched Parrot’s repository branch from rolling to testing and I saw among the updates a new libc. I’ll have to test it out when I get back from shopping.

I still recommend the version from pip3. At least it works fine. Well i hope you can help me to check libvirt error and how to install ubridge. The libvirt likely belongs to qemu thing or at least i saw something about it before (maybe virt-manager?) so i don’t know much about this.

This is madness! LOL. I’ll see if I can get the pip3 GNS3 (which I’ve used before successfully) working with the ubridge from the ppa next.


It worked using the pip3 packages and the ppa’s ubridge! I’ll have to downgrade the VPCS package though.


I don’t know if you were able to follow all of the above. Do you already have Cisco cert(s)? If you are going for your CCNA, Packet Tracer is more suited for the exam.

GNS3 cannot virtualize switches (VLANs, STP, etc.), wireless and many other things on the CCNA while Packet Tracer can. It’s not until you go after some advanced Cisco specialist certification when some of the advanced features of GNS3 are needed. Maybe you know all this already.

GNS 3 should be on repository now. At least on rolling-testing branch
@Masmer would you like to try it on repo :smiley:
p/s: ubridge is on repo as well

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@dmknght looking good. Had to add Qt5 dependencies manually (PyQt5.QtSvg PyQt5.QtWebSockets).

Parrot 5 Beta 8

oh really? is that runtime dependencies? and you send me the apt package name please? i’ll add them in control file


python3-pyqt5.qtsvg python3-pyqt5.qtwebsockets

Thank a lot! On Parrot XFCE home, those packages were installed. I guess because other plugins / packages are using them and that’s why I missed those dependencies :smiley: