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Archana Shinde amshinde

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amshinde / slirp4netns.md
Created March 27, 2019 18:12 — forked from mcastelino/slirp4netns.md
slirp4netns: How does it work

Create a process with its own network and pid namespace

$ unshare --user --map-root-user --net --mount
[root@incensed-gawain ~]# echo $$
2646

Run the slirp process on the host

@amshinde
amshinde / mlgre.md
Created November 12, 2018 19:36 — forked from mcastelino/mlgre.md
Setting up a overlay network using point to multi-point GRE tunnels

Setting up a overlay network using point to multi-point GRE tunnels

Multi-Point GRE Tunnels

Typically VxLAN is used to setup a point to multi-point overlay networks. However GRE also offers a similar capability which is often not heavily used. This document calls out how to setup an effient overlay mesh network to link up multiples sits together using multi point GRE tunnels.

Setup

The setup used in this case assumes there is a need to link three sites hosting three different subnets together using a simple overlay mesh network.

@amshinde
amshinde / iptables-cheatsheet.md
Created November 9, 2018 22:43 — forked from mcastelino/iptables-cheatsheet.md
iptables-cheatsheet

The netfilter hooks in the kernel and where they hook in the packet flow

The figure below calls out

  • The netfilter hooks
  • The order of table traversal
@amshinde
amshinde / VFIO_nested.md
Created October 29, 2018 17:13 — forked from mcastelino/VFIO_nested.md
QEMU VFIO in Nested VM vIOMMU

How to use VFIO to assign a device to nested VM

  • Here the vfio-pci device is passed in into the L1 VM
  • The L1 VM is setup with kernel_irqchip=split
  • The L0 exposes a virtual IOMMU to the L1 VM
qemu-system-x86_64 \
    -machine q35,accel=kvm,kernel_irqchip=split \
    -enable-kvm \
@amshinde
amshinde / macvlan_ipvlan_driver_notes.md
Last active April 4, 2019 01:16 — forked from nerdalert/macvlan_ipvlan_driver_notes.md
Macvlan ipvlan
@amshinde
amshinde / tc mirroring.md
Created October 19, 2018 17:10 — forked from mcastelino/tc mirroring.md
Using tc redirect to connect a virtual machine to a container network

Connecting a veth device to tap

  • veth device from CNI/CNM plugin: eth0
  • tap device that connects to the VM: tap0

Redirecting traffic between the two devices

tc qdisc add dev eth0 ingress
tc filter add dev eth0 parent ffff: protocol all u32 match u8 0 0 action mirred egress redirect dev tap0
@amshinde
amshinde / graphics-vfio.md
Created October 11, 2018 18:03 — forked from egernst/graphics-vfio.md
Passing graphics card to a Clear Container

Passing a graphics card to a Clear Container

Host system setup:

The directions below are specific to an Ubuntu 16.04 host system equipped with a GeForce GTX 550 Ti graphics card. While the process should be the same, YMMV.

  1. Make sure your system supports IOMMU groups

todo -- get directions from SRIOV page