Cali interface per pod

cali_interface_per_pod.sh

#!/bin/bash
# Tested on: Calico, Flannel, Canal
# Based on https://github.com/moby/moby/issues/17064#issuecomment-294020260, thanks!
# Sample output:
#PODIP     MAC .              CONTAINERNAME .                                                                      CONTAINERID  HOSTINTERFACE        HOSTINTERFACEID 
#10.42.0.4 2a:9f:ae:37:72:1d /k8s_POD_kube-dns-7588d5b5f5-nfg7m_kube-system_d7bbd8b9-23c6-11e9-ae75-f2e6ffededb1_0 59c6dc5e0686 cali38ead6f8cf5@if3: 60                                                                                                                               
#10.42.0.3 8e:2f:6b:2a:39:b3 /k8s_POD_kube-dns-autoscaler-5db9bbb766-q9mgx_kube-system_d8448b72-23c6-11e9-ae75-f2e6ffededb1_0 52a2bc450eb5 calia637e63e14c@if3: 59                                                                                                                    
#10.42.0.5 2e:d4:e4:bf:5b:65 /k8s_POD_default-http-backend-797c5bc547-scms7_ingress-nginx_de34fbda-23c6-11e9-ae75-f2e6ffededb1_0 4bb45486b56e cali2f9425798d9@if3: 61                                                                                                                 
#10.42.0.2 6a:fb:30:47:93:cf /k8s_POD_metrics-server-97bc649d5-5txbx_kube-system_da8d90c0-23c6-11e9-ae75-f2e6ffededb1_0 039ee9406434 calicfa1484b96a@if3: 58                 

function cali_interface_for_container() {

  container_name=$(docker inspect --format='{{.Name}}' "${1}")

  # Get the process ID for the container named ${1}:
  local pid=$(docker inspect -f '{{.State.Pid}}' "${1}")

  # Make the container's network namespace available to the ip-netns command:
  mkdir -p /var/run/netns
  ln -sf /proc/$pid/ns/net "/var/run/netns/${1}"

  # Get the interface index of the container's eth0:
  local podip=$(ip netns exec $1 ip addr show eth0 | grep "inet\b" | awk '{print $2}' | cut -d/ -f1)
  local index=$(ip netns exec $1 ethtool -S eth0 2>/dev/null | grep peer_ifindex | awk '{ print $2 }')
  local mac=$(ip netns exec $1 ip addr show eth0 | grep ether | awk '{ print $2 }')

  # Write the name of the veth interface to stdout:
  VETH=$(ip link show | grep "^${index}:" | awk '{ print $2 }')

  if [ "x$VETH" != "x" ]; then
    echo "$(echo $podip) $mac $container_name $1 $VETH $index"
  fi

  # Clean up the netns symlink, since we don't need it anymore
  rm -f "/var/run/netns/${1}"
}

if [ "$#" -eq 0 ]; then
    for docker_container in `docker ps -q --filter=name=POD`; do
      cali_interface_for_container $docker_container
    done
fi

if [ "$#" -eq 1 ]; then
  cali_interface_for_container $1
fi