Platform: Asuswrt-Merlin using kernel 2.6.36
How do you install/load the iptables "rpfilter" module in a bash script ?
As far as I know that netfilter module is not supported on kernels 2.6.x. The support was added starting with kernel 3.x
Please check the link bellow:
https://www.snbforums.com/threads/how-to-load-iptables-rpfilter-module.39842/
Related
i'm trying to use QEMU 5.x for research.
I got QEMU 5.2 source code from qemu.org and installed following instructions.
However, when i tried to run VM by this command:
qemu-system-x86_64 \
-monitor stdio \
--enable-kvm \
-m 4096 \
-cdrom ubuntu-20.04.iso \
-drive file=img.qcow,if=virtio \
-boot c
-rtc base=localtime \
-device virtio-keyboard-pci \
-vga virtio \
then the following texts are printed:
QEMU 5.2.0 monitor - type 'help' for more information
(qemu) VNC server running on 127.0.0.1:5900
then nothing shows up, while QEMU 4.x (used before) pops up a window showing guest ubuntu's GUI.
I'm using ubuntu 20.04. Hope anyone has breakthrough for this..
The message says that this QEMU is using the VNC protocol for graphics output. You can connect a VNC client to the 127.0.0.1:5900 port that it tells you about to see the graphics output.
If what you wanted was a native X11 window (GTK), then the problem is probably that you didn't have the necessary libraries installed to build the GTK support. QEMU's configure script's default behaviour is "build all the optional features that this host has the libraries installed for, and omit the features where the libraries aren't present". So if you don't have any of the GTK/SDL etc libraries when you build QEMU, the only thing you will get in the resulting QEMU binary is the lowest-common-denominator VNC support. If you want configure to report an error for a missing feature then you need to pass it the appropriate --enable-whatever option to force the feature to be enabled (in this case, --enable-gtk).
If you're running on Ubuntu and your apt sources.list file has deb-src lines in it, the easiest way to install all the dependencies that would get you the same feature list as the real Ubuntu QEMU package is to run "apt build-dep qemu". I recommend that you do that and then re-build QEMU, passing --enable-gtk to configure so you can confirm that the necessary dependencies were installed.
I am installing DPDK in Open vSwitch (OVS).
https://github.com/openvswitch/ovs/blob/master/INSTALL.DPDK.md
The problem is when I ran 2 commands like this.
export DB_SOCK=/usr/local/var/run/openvswitch/db.sock
sudo ovs-vswitchd --dpdk -c 0x1 -n 4 -- unix:$DB_SOCK --pidfile --detach
I got error:
ovs-vswitchd: DPDK support not built into this copy of Open vSwitch.
Could anyone please explain to me how to fix this pronlem.
Thank in advance for your help!
You need to compile OVS against DPDK with DPDK support enabled (--with-dpdk):
export DPDK_BUILD=$DPDK_DIR/x86_64-native-linuxapp-gcc/
./configure --with-dpdk=$DPDK_BUILD
make
make install
I have a question about the running of OpenFlow switch:
If we want to run OpenFlow on such a PC or a router to work as an OpenFlow switch, what should we do for that?, and is the CPU type or platform of that device important? does it make any difference?
thanks in advance.
Before you try anything on a PC, Install Open vSwitch on a VM(probably Ubuntu) and try its OpenFlow functionality.
To install Open vSwitch(OVS) on ubuntu,
sudo apt-get install openvswitch-switch
You could get a controller like Floodlight or Ryu SDN framework to act as the controller for your switch.
Here is an OpenFlow tutorial. It is outdated but still informative http://archive.openflow.org/wk/index.php/OpenFlow_Tutorial
Or you could also try mininet as #EricSorensen suggested in the previous answer. Mininet allows you to simulate a network with hosts and switches.
While using mininet, you could use its inbuilt 'nox' controller. I'd prefer floodlight though.
Hope it helps!
This is all you need: http://mininet.org/
Check the downloads and tutorial. Use either a Virtual Machine, or native install from source (on Linux)
you can install openvswitch or use ofsoftswitch13 from https://github.com/CPqD/ofsoftswitch13 in a linux based PC with at least two physical interfaces.so that the packet routing can see.
Also using mininet https://github.com/mininet/mininet can run OF (for this one interface is enough) which supports the creation of various network topologies.
As suggested for testing you can simply do a apt-get install or similar on most recent Linux distros. There are two components to openvswitch, a kernel module and the user space openvswitch. The user space process does not require any specific number of cores or processor type and for the most part you can do with less than a core.
Apart from ovs you also need ovsdb, which apt-get install or similar will automatically set up for you (hence the easiest way to go about it). Again pretty lightweight its just a json key-value db.
For the controller there are a lot of options but for playing around you can use the built in command line tools as well.
ovs-apptctl: To setup the switch http://openvswitch.org/support/dist-docs/ovs-appctl.8.txt
ovs-oftcl: To add/mod/flows http://openvswitch.org/support/dist-docs/ovs-ofctl.8.txt
ovs-dpctl: To see the kernel flows
I would highly recommend getting a feel for the command line tools, OpenFlow commands and how flows work before picking Pox, Daylight etc.
Apart from mininet there is also Oftest (https://github.com/floodlight/oftest) that is primarily used to write tests for openflow but its pretty useful to learn and debug issues in a constrained environment.
Running OpenvSwitch
If you want to build OpenvSwitch with bare metal, I suggest you use official tarball to install OpenvSwitch daemon.
Please follow this step:
#/bin/bash
# In root permission
aptitude install dh-autoreconf libssl-dev openssl
wget http://openvswitch.org/releases/openvswitch-2.4.0.tar.gz
tar zxvf openvswitch-2.4.0.tar.gz && cd openvswitch-2.4.0
./boot.sh
./configure # If you want to build kernel module, please append --with-linux=/lib/modules/`uname -r`/build
make modules_install
modprobe gre
modprobe openvswitch
modprobe livcrc32c
ovsdb-tool create /usr/local/etc/openvswitch/conf.db /usr/local/share/openvswitch/vswitch.ovsschema
ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \
--remote=db:Open_vSwitch,Open_vSwitch,manager_options \
--pidfile --detach --log-file
ovs-vsctl --no-wait init
ovs-vswitchd --pidfile --detach --log-file
You can use ovs-vsctl show of ovs-ofctl show to check OpenvSwitch status. Next step, we need to add physical or logical (likes veth pair) interfaces to OpenvSwitch bridge
# Create OpenvSwitch is named 'ovs-br'
ovs-vsctl add-br ovs-br
# Add interface to OpenvSwitch bridge
# If you want to check, please use `ovs-vsctl` to check again.
ovs-vsctl add-port ovs-br eth0
# Set OpenFlow controller
# You should ready one controller
# If not, I have two installation solutions can give you
# Ryu installation: https://github.com/sdnds-tw/ryu-installer
# ONOS installation: https://github.com/pichuang/onos-ansible
ovs-vsctl ovs-br set-controller tcp:x.x.x.x:6653
# Use ovs-vsctl to check controller attribute is UP
Once you let another server(here we call it controller) to determine the packet forwarding behavior of your local machine (here it is your PC), it turns into so-called SDN mechanism. So it's not relevant what kind of CPU or hardware you are choosing, basically, you can consider SDN as a software solution.
For the process to install the SDN-enabled software, you can choose open vswitch which has been answered in the above posts.
I compiled the Linux kernel (version 2.6.32) using the Emdebian ARM toolchain. Downloaded the initrd from Aurel's personal FTP server hosted on Debian here.
The ran qemu like so:
qemu-system-arm -M versatilepb -kernel zImage -hda hda.img -initrd initrd_versatile.gz -append "root=/dev/ram" -m 1024
Yet it fails with qemu reporting:
mount: mouting none of /run failed invalid argument.
Keen to hear if someone has something to say about this. As I search for it, could someone also let me know if it is possible to use an off the shelf initrd or is it related to the kernel version being run?
I was able to run the machine by cross compiling busybox, creating a cpio archive image and then using it like so:
qemu-system-arm -M versatilepb -m 128M -kernel zImage -initrd rootfs.img -append "root=/dev/ram rdinit=/bin/sh console=tty1"
Now that Ive got it working Ill investigate what those arguments actually mean.
I'm trying to get started on libvirt with VirtualBox as a virtualization solution. I installed everything and VirtualBox itself is running when using their VBoxHeadless command.
However, libvirt fails to connect to VirtualBox:
# virsh -c vbox:///session
libvir: error : could not connect to vbox:///session
error: failed to connect to the hypervisor
I could not find any hints in the libvirt documentation that point to whether I have to make any domain specific configuration before using virsh.
Does anyone have a hint? Or even better, maybe a tutorial that works through the way of using libvirt, virsh or it's APIs (my later goal) from the ground up.
If you are doing this on Ubuntu, then the problem is their libvirt package is built without VirtualBox support.
You can rebuild the package with support very easily. Something like:
apt-get source -d libvirt
sudo apt-get build-dep libvirt
dpkg-source -x libvirt*dsc
Go into the libvirt directory and edit debian/rules so that instead of --without-vbox it says --with-vbox. You can add an entry to the top of debian/changelog so the package is compiled as a different version (e.g., append ~local1 to the version).
dpkg-buildpackage -us -uc -b -rfakeroot
You'll get new .debs built in the directory above. Use dpkg -i to install the relevant ones (libvirt0, libvirt0-bin, and whatever else you want).
Double-check whether or not you have write access to /var/run/libvirt/libvirt-sock.
The socket file should have permissions similar to:
$ sudo ls -la /var/run/libvirt/libvirt-sock
srwxrwx--- 1 root libvirtd 0 2010-08-24 14:54 /var/run/libvirt/libvirt-sock
I think it could be helpful also to increase the libvirt logging capabilities by running this in your shell:
export LIBVIRT_DEBUG=1
There is Ubuntu PPA for libvirt with VirtualBox support: https://launchpad.net/~cxl/+archive/ubuntu/libvirt