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Archana Shinde amshinde

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amshinde / README.md
Created July 11, 2022 20:29 — forked from smoser/README.md
backdoor-image

backdoor-image

Description

backdoor-image can be used to easily add user with passwordless sudo access to a image or a root filesystem.

Operating on an image requires the 'mount-image-callback' tool from cloud-utils. That can be installed on ubuntu via apt-get install -qy cloud-image-utils.

@amshinde
amshinde / kcgroups.md
Created April 24, 2023 21:23 — forked from mcastelino/kcgroups.md
Kubernetes and cgroups Resource Management/Static cpuManagerPolicy/Memory and Resource Isolation & Scheduling

Overview

The goal of this document to cover all aspects of Kubernetes management, including how resources are expressed, constrained and accounted for. This started a way to ensure that alternate container runtime implementation like Kata containers will behave from a resource accounting and consumption point of view in the same manner as runc.

Location of the latest version of this document: https://gist.github.com/mcastelino/b8ce9a70b00ee56036dadd70ded53e9f

If you do not understand cgroups please refer to a quick primer at the bottom of this document. This will help you understand how the resource enforcement actually works.

Kubernetes Resource Management

@amshinde
amshinde / canal.md
Created April 24, 2023 21:26 — forked from krsna1729/canal.md
tracing network stack for MACVLAN IPVLAN

This is only a trace on vxlan interface on the host. not from within container namespace

  ping-26819 [001]  3678.931358: fib_table_lookup:     table 254 oif 0 iif 1 proto 17 0.0.0.0/40784 -> 10.244.2.4/1025 tos 0 scope 0 flags 0 ==> dev flannel.1 gw 10.244.2.0 src 10.244.0.0 err 0
  ping-26819 [001]  3678.931387: fib_table_lookup:     table 254 oif 0 iif 1 proto 17 10.244.0.0/40784 -> 10.244.2.4/1025 tos 0 scope 0 flags 0 ==> dev flannel.1 gw 10.244.2.0 src 10.244.0.0 err 0
  ping-26819 [001]  3678.931468: fib_table_lookup:     table 254 oif 0 iif 1 proto 1 0.0.0.0/0 -> 10.244.2.4/0 tos 0 scope 0 flags 0 ==> dev flannel.1 gw 10.244.2.0 src 10.244.0.0 err 0
  ping-26819 [001]  3678.931485: fib_table_lookup:     table 255 oif 0 iif 0 proto 0 0.0.0.0/0 -> 10.244.2.4/0 tos 0 scope 0 flags 0 ==> dev flannel.1 gw 10.244.2.0 src 10.244.0.0 err 0
  ping-26819 [001]  3678.931499: net_dev_queue:        dev=flannel.1 skbaddr=0xffff919236689800 len=98
  ping-26819 [001]  3678.931500: net_dev_start_xmit:   dev=flann
@amshinde
amshinde / bpftrace.md
Created April 24, 2023 21:28 — forked from krsna1729/bpftrace.md
bpftrace one-liners skbdump 
$ sudo bpftrace -e 'tracepoint:napi:napi_poll /comm == "ping"/ { printf("%s\n", comm) }'
Attaching 1 probe...
ping
ping
ping
$ sudo bpftrace -e 'tracepoint:napi:napi_poll /comm == "ping"/ { printf("%d\n", args->work) }'
@amshinde
amshinde / qemu_direct_kernel_boot_disk.md
Created April 25, 2023 18:47 — forked from mcastelino/qemu_direct_kernel_boot_disk.md
QEMU Direct Kernel Boot into a disk image
#!/bin/bash
# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
# ex: ts=8 sw=4 sts=4 et filetype=sh
VMN=${VMN:=1}
NEMU=~/build-x86_64/x86_64-softmmu/qemu-system-x86_64
sudo $NEMU \
-trace events=/tmp/events \
@amshinde
amshinde / Nested_VFIO.md
Created May 17, 2023 06:27 — forked from sboeuf/Nested_VFIO.md
How to test VFIO with virtio-net-pci device

Prepare the host

Get the image clear-XXXXX-kvm.img

wget https://download.clearlinux.org/releases/30080/clear/clear-30080-kvm.img.xz
unxz clear-30080-kvm.img.xz

Add intel_iommu=on to the kernel boot parameters

mkdir mount_dir