Merge pull request #435 from cloudnull/Issue434

Creates a lxc-system-manage script for common operational tasks.
This commit is contained in:
Hugh Saunders 2014-10-29 08:44:58 +00:00
commit 82e65abbba
2 changed files with 356 additions and 0 deletions

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#!/usr/bin/env bash
# Copyright 2014, Rackspace US, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# This sciprt was built for the express purpose of managing LXC on a
# host. The functions within this script provide for common operations
# that may be required when working with LXC in production.
export USE_LXC_BRIDGE="true"
export LXC_BRIDGE="lxcbr0"
export LXC_ADDR="10.0.3.1"
export LXC_NETMASK="255.255.255.0"
export LXC_NETWORK="10.0.3.0/24"
export LXC_DHCP_RANGE="10.0.3.2,10.0.3.254"
export LXC_DHCP_MAX="253"
export LXC_DHCP_CONFILE=""
export VARRUN="/run/lxc"
export LXC_DOMAIN=""
function warn() {
echo -e "\e[0;35m${@}\e[0m"
}
function info() {
echo -e "\e[0;33m${@}\e[0m"
}
function success() {
echo -e "\e[0;32m${@}\e[0m"
}
function remove_rules() {
success "Removing LXC IPtables rules."
# Remove rules from the INPUT chain
iptables ${USE_IPTABLES_LOCK} -D INPUT -i "${LXC_BRIDGE}" -p udp --dport 67 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -D INPUT -i "${LXC_BRIDGE}" -p tcp --dport 67 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -D INPUT -i "${LXC_BRIDGE}" -p udp --dport 53 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -D INPUT -i "${LXC_BRIDGE}" -p tcp --dport 53 -j ACCEPT
# Remove rules from the FORWARDING chain
iptables ${USE_IPTABLES_LOCK} -D FORWARD -i "${LXC_BRIDGE}" -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -D FORWARD -o "${LXC_BRIDGE}" -j ACCEPT
# Remove rules from the nat POSTROUTING chain
iptables ${USE_IPTABLES_LOCK} -t nat \
-D POSTROUTING \
-s "${LXC_NETWORK}" ! \
-d "${LXC_NETWORK}" \
-j MASQUERADE || true
# Remove rules from the mangle POSTROUTING chain
iptables ${USE_IPTABLES_LOCK} -t mangle \
-D POSTROUTING \
-o "${LXC_BRIDGE}" \
-p udp \
-m udp \
--dport 68 \
-j CHECKSUM \
--checksum-fill
}
function add_rules() {
success "Creating LXC IPtables rules."
set -e
# Set ip_prwarding
sysctl -w net.ipv4.ip_forward=1 > /dev/null 2>&1
# Add rules from the INPUT chain
iptables ${USE_IPTABLES_LOCK} -I INPUT -i "${LXC_BRIDGE}" -p udp --dport 67 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -I INPUT -i "${LXC_BRIDGE}" -p tcp --dport 67 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -I INPUT -i "${LXC_BRIDGE}" -p udp --dport 53 -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -I INPUT -i "${LXC_BRIDGE}" -p tcp --dport 53 -j ACCEPT
# Add rules from the FORWARDING chain
iptables ${USE_IPTABLES_LOCK} -I FORWARD -i "${LXC_BRIDGE}" -j ACCEPT
iptables ${USE_IPTABLES_LOCK} -I FORWARD -o "${LXC_BRIDGE}" -j ACCEPT
# Add rules from the nat POSTROUTING chain
iptables ${USE_IPTABLES_LOCK} -t nat \
-A POSTROUTING \
-s "${LXC_NETWORK}" ! \
-d "${LXC_NETWORK}" \
-j MASQUERADE
# Add rules from the mangle POSTROUTING chain
iptables ${USE_IPTABLES_LOCK} -t mangle \
-A POSTROUTING \
-o "${LXC_BRIDGE}" \
-p udp \
-m udp \
--dport 68 \
-j CHECKSUM \
--checksum-fill
}
function cleanup() {
# Clean up everything
remove_rules
# Set the lxc bridge interface down
ip link set "${LXC_BRIDGE}" down || true
# Remove the lxc bridge interface
brctl delbr "${LXC_BRIDGE}" || true
}
function pre_up() {
# Create the run directory if needed.
if [[ ! -d "${VARRUN}" ]];then
mkdir -p "${VARRUN}"
fi
# Source the lxc defaults
if [[ -f "/etc/default/lxc" ]]; then
source "/etc/default/lxc"
fi
# Set the lock type where applicable
use_iptables_lock="-w"
iptables -w -L -n > /dev/null 2>&1 || use_iptables_lock=""
}
function start_dnsmasq() {
set -e
success "Starting LXC dnsmasq."
dnsmasq "${LXC_DOMAIN_ARG}" -u lxc-dnsmasq \
--strict-order \
--bind-interfaces \
--pid-file="${VARRUN}/dnsmasq.pid" \
--conf-file="${LXC_DHCP_CONFILE}" \
--listen-address "${LXC_ADDR}" \
--dhcp-range "${LXC_DHCP_RANGE}" \
--dhcp-lease-max="${LXC_DHCP_MAX}" \
--dhcp-no-override \
--except-interface="lo" \
--interface="${LXC_BRIDGE}" \
--dhcp-leasefile="${DHCP_LEASE_FILE}" \
--dhcp-authoritative
}
function start_containers_nicely() {
set -e
# Stop all containers on a host
success "Starting all containers."
for container in $(lxc-ls); do lxc-start -d -n "${container}"; done
}
function stop_containers_nicely() {
# Stop all containers on a host
warn "Stopping all containers."
for container in $(lxc-ls); do lxc-stop -n "${container}"; done
}
function stop_containers_with_fire() {
# Stop all containers on a host
warn "Stopping all containers with fire."
for container in $(lxc-ls); do lxc-stop -k -n "${container}"; done
}
function start_networks() {
set -e
success "Building the LXC container network."
# Create lxc bridge
brctl addbr "${LXC_BRIDGE}"
# Set the lxc bridge up
ip link set "${LXC_BRIDGE}" up || true
# Assign an address to the lxc bridge
ip addr add "${LXC_ADDR}"/"${LXC_NETMASK}" dev "${LXC_BRIDGE}"
add_rules
LXC_DOMAIN_ARG=""
if [ -n "$LXC_DOMAIN" ]; then
LXC_DOMAIN_ARG="-s $LXC_DOMAIN -S /$LXC_DOMAIN/"
fi
# Start DNS mask
DHCP_LEASE_FILE="/var/lib/misc/dnsmasq.${LXC_BRIDGE}.leases"
start_dnsmasq
}
function stop_dnsmasq() {
if [[ -f "${VARRUN}/dnsmasq.pid" ]];then
PID="$(cat ${VARRUN}/dnsmasq.pid)"
if [[ "${PID}" ]];then
warn "Stopping LXC dnsmasq."
kill -9 "${PID}" || true
fi
rm -f "${VARRUN}/dnsmasq.pid"
fi
}
function stop_networks() {
warn "Destroying the LXC container network."
cleanup
stop_dnsmasq
}
function remove_down_veth() {
info "Getting a list of all DOWN veth interfaces"
VETHPAIRS="$(ip link list | grep veth | grep "state DOWN" | awk '/veth/ {print $2}' | sed 's/\://g')"
if [[ "$VETHPAIRS" ]];then
warn "Removing all DOWN veth interfaces"
for veth in $VETHPAIRS; do ip link delete dev "${veth}"; done
else
success "No DOWN veth interfaces to remove"
fi
}
function flush_cache() {
warn "Flushing network cache"
ip -s -s neigh flush all
}
# Run through the base app setup
pre_up
# Check function
case "$1" in
containers-start)
start_containers_nicely
;;
containers-stop)
stop_containers_nicely
;;
containers-force-stop)
stop_containers_with_fire
;;
containers-restart)
stop_containers_nicely
start_containers_nicely
;;
containers-force-restart)
stop_containers_with_fire
start_containers_nicely
;;
system-tear-down)
stop_containers_nicely
remove_down_veth
stop_networks
flush_cache
;;
system-force-tear-down)
stop_containers_with_fire
remove_down_veth
stop_networks
flush_cache
;;
system-start-up)
start_networks
start_containers_nicely
;;
system-rebuild)
stop_containers_nicely
remove_down_veth
stop_networks
flush_cache
start_networks
start_containers_nicely
;;
system-force-rebuild)
stop_containers_with_fire
remove_down_veth
stop_networks
flush_cache
start_networks
start_containers_nicely
;;
dnsmasq-start)
start_dnsmasq
;;
dnsmasq-stop)
stop_dnsmasq
;;
dnsmasq-restart)
stop_dnsmasq
start_dnsmasq
;;
iptables-create)
add_rules
;;
iptables-remove)
remove_rules
;;
iptables-recreate)
remove_rules
add_rules
;;
veth-cleanup)
remove_down_veth
;;
flush-net-cache)
flush_cache
;;
*)
info 'Management of internal LXC systems and processes:'
echo '
containers-start Start all containers.
containers-stop Stop all containers.
containers-restart Stop all containers and then Start them.
containers-force-stop Force Stop all containers.
containers-force-restart Force Stop all containers and then Start them.
system-start-up Start up everything that LXC needs to
operate, including the containers, dnsmasq,
LXC bridge, and IPtables.
system-tear-down Tear down everything LXC on this system.
This will remove all all IPtables rules, kill
dnsmasq, remove the LXC bridge, stops all
containers, removes DOWN veth interfaces,
and flushes the net cache.
system-force-tear-down Force tear down everything LXC on this system.
This will remove all all IPtables rules, kill
dnsmasq, remove the LXC bridge, stops all
containers, removes DOWN veth interfaces,
and flushes the net cache.
system-rebuild Rebuild the LXC network, IPtables, dnsmasq,
removes DOWN veth interfaces, flushes the
net cache, and restarts all conatiners.
system-force-rebuild Force rebuild the LXC network, IPtables, dnsmasq,
removes DOWN veth interfaces, flushes the
net cache, and restarts all conatiners.
dnsmasq-start Start the LXC dnsmasq process.
dnsmasq-stop Stop the LXC dnsmasq process.
dnsmasq-restart Restart the LXC dnsmasq process.
iptables-create Create the LXC IPtables rules.
iptables-remove Remove the LXC IPtables rules.
iptables-recreate Recreate the LXC IPtables rules.
veth-cleanup Remove all DOWN veth interfaces from a system.
flush-net-cache Flush the hosts network cache. This is usful if
IP addresses are being recycled on to containers
from other hosts.
'
;;
esac

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# Ensure apparmor reindex runs before other things that may fail # Ensure apparmor reindex runs before other things that may fail
- meta: flush_handlers - meta: flush_handlers
- name: Drop lxc-system-manage script
copy:
src: "lxc-system-manage"
dest: "/usr/local/bin/lxc-system-manage"
owner: "root"
group: "root"
mode: "0755"