Steve's Solaris/Linux experiences: Systemd

Interested in getting OpenStack up and running within few hours in the easiest possible way? Then Packstack is most probably your friend. Indeed, Packstack is a utility which leverages on Puppet modules to deploy various parts of OpenStack on multiple pre-installed servers over SSH automatically. I've been through a cycle of building/destroying my OpenStack Labs by using this tool and I'm willing to share below a Kickstart File which fully automate such type of Installation (OpenStack using PackStack with an Existing External Network). The initial process on which I built this KickStart Installation is well documented here. My main aim here is to be able to reference a Single Kickstart File during my RHEL/CentOS 7 Installation and have OpenStack Installed and partly configured without manual Intervention (except for a reboot that I preferred not to automate :-) ).

The same Kickstart File can also be used as a Template for RHEL7/CentOS7 (or any other Systemd-based's distribution), especially if there's a need to run some script (or any other program) during the first boot (after OS installation) of the System (see the %post section).
In fact, in this Kickstart File I've edited and created a Systemd service that will run only once after the first boot and delete itself.
I was used to do that on previous RHEL/CentOS (RHEL6...) by leveraging on /etc/rc.local. Though there’s still /etc/rc.local on RHEL7,It is highly advisable to create own systemd services or udev rules to run scripts during boot instead of using that file.

Note that after the initial reboot, Packstack Configuration Progress can be followed using journalctl (journalctl -f -u pacstack_installation.service)

Few Things that are specific to this Kickstart:
System Hostname: stiv-opsctr01
System IP: 192.168.0.21/24
System GW: 192.168.0.1
DNS1 IP: 192.168.0.30
DNS2 IP: 192.168.0.31
PROXY and Install Server (I'm using proxy for Internet Access) : 192.168.0.33

My Kickstart File:

#version=RHEL7
# System authorization information
auth --enableshadow --passalgo=sha512

# SELinux configuration
selinux --disabled

# Use URL to install installation media
url --url=http://192.168.0.33/media_centos7u1/

# Use text install
text

# Run the Setup Agent on first boot
firstboot --disable
ignoredisk --only-use=sda

# Keyboard layouts
keyboard --vckeymap=us --xlayouts='us'

# System language
lang en_US.UTF-8

# Network information
network  --bootproto=static --device=eno49 --gateway=192.168.0.1 --ip=192.168.0.21 --nameserver=192.168.0.30,192.168.0.31 --netmask=255.255.255.0 --noipv6 --activate --hostname=stiv-opsctr01
network  --bootproto=dhcp --device=eno50 --onboot=off --ipv6=auto
network  --bootproto=dhcp --device=eno51 --onboot=off --ipv6=auto
network  --bootproto=dhcp --device=eno52 --onboot=off --ipv6=auto

# Root password
rootpw --iscrypted $6$bimdfXrAP9SXO64e$QzN5e44MdaqVF79IW9DcGGTmAg.6SBp8ktGyw3q0ceu1zp.GBjdEEoU82y8NeEePK6WJpq3Omru.YigsUy.

# System timezone
timezone Africa/Douala --isUtc --nontp

# System bootloader configuration
bootloader --append=" crashkernel=auto" --location=mbr --boot-drive=sda

# Partition clearing information
clearpart --all --initlabel --drives=sda

# Disk partitioning information
part /boot --fstype="xfs" --ondisk=sda --size=500
part pv.26 --fstype="lvmpv" --ondisk=sda --size=163840  --grow --asprimary
volgroup centos --pesize=4096 pv.26
logvol swap  --fstype="swap" --size=51200 --name=swap --vgname=centos
logvol /home  --fstype="xfs" --size=20480 --name=home --vgname=centos
logvol /  --fstype="xfs" --size=51200 --name=root --vgname=centos --grow

%packages
@core
kexec-tools

%end

%addon com_redhat_kdump --enable --reserve-mb='auto'

%end

# Start of the %post section with logging into /root/ks-post.log
%post --log=/root/ks-post.log --interpreter=/usr/bin/bash
exec < /dev/tty6 > /dev/tty6
chvt 6
clear
echo "################################"
echo "# Running Post Configuration   #"
echo "################################"

set -x

# Make sure no Interface uses NetworkManager and disable it
for nic in $(grep -l NM_CONTROLLED.*yes /etc/sysconfig/network-scripts/ifcfg-*) 
do
cp $nic ${nic}.bak
sed -i "s/NM_CONTROLLED=yes/NM_CONTROLLED=no/"  $nic
done
systemctl disable NetworkManager

# Disable IPv6 in sysctl and yum.conf / it was already disabled on Interface
echo "net.ipv6.conf.all.disable_ipv6 = 1" >> /etc/sysctl.conf
echo "net.ipv6.conf.default.disable_ipv6 = 1" >> /etc/sysctl.conf
sysctl -p
echo "ip_resolve=4" >> /etc/yum.conf

# Set Proxy (only if needed) dynamically and in /etc/profile as well as yum.conf
export http_proxy=http://"192.168.0.33":"3128"/
export https_proxy=http://"192.168.0.33":"3128"/
echo 'export http_proxy=http://"192.168.0.33":"3128"/' >> /etc/profile
echo 'export https_proxy=http://"192.168.0.33":"3128"/' >> /etc/profile
echo 'proxy=http://192.168.0.33:3128/' >> /etc/yum.conf

# Populate hosts file
cat <<eof >/etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

# Public IP
192.168.0.21     stiv-opsctr01 stiv-opsctr01.stiv.local
EOF

# Install my dear vim
yum install -y vim

# Install Packstack
yum install -y https://rdoproject.org/repos/rdo-release.rpm
yum install -y openstack-packstack

# Run Packstack after the reboot as a Systemd Service
cat > /root/packstack_install.sh << EOFPACKSTACK
#!/bin/bash

set -x

# Run Packstack and Configure 
packstack --allinone --provision-demo=n

# Configure External Network
cat <<EOF >/etc/sysconfig/network-scripts/ifcfg-br-ex
DEVICE=br-ex
DEVICETYPE=ovs
TYPE=OVSBridge
BOOTPROTO=static
IPADDR=192.168.0.21
NETMASK=255.255.255.0
GATEWAY=192.168.0.1 
DNS1=192.168.0.30
DNS2=192.168.0.31
ONBOOT=yes
EOF

cat <<eof >/etc/sysconfig/network-scripts/ifcfg-eno49 
TYPE=Ethernet
NAME=eno49
DEVICE=eno49
ONBOOT=yes
TYPE=OVSPort
DEVICETYPE=ovs
OVS_BRIDGE=br-ex
EOF

# Go to /root
cd /root

# Restart Network Service
systemctl restart network

# Define Logical Name for our physical L2 Segment (extnet)
openstack-config --set /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini ovs bridge_mappings extnet:br-ex

# Overcome a packstack deployment bug where only vxlan is made available
openstack-config --set /etc/neutron/plugin.ini ml2 type_drivers vxlan,flat,vlan

# Restart Services
/bin/systemctl restart network.service
/bin/systemctl restart neutron-openvswitch-agent.service
/bin/systemctl restart neutron-server.service

# Create Neutron External Network / unset proxy as API is available on http and allocate Pool IP
unset http_proxy
unset https_proxy
source /root/keystonerc_admin
neutron net-create external_network --provider:network_type flat --provider:physical_network extnet  --router:external --shared
neutron subnet-create --name public_subnet --enable_dhcp=False --allocation-pool=start=192.168.0.200,end=192.168.0.230 --gateway=192.168.0.1 external_network 192.168.0.0/24

# Neutron / Create Router
neutron router-create router1
neutron router-gateway-set router1 external_network

# Neutron / Create Private Network
neutron net-create private_network
neutron subnet-create --name private_subnet private_network 192.168.100.0/24

# Neutron / Connect Private Network to Public through the Router
neutron router-interface-add router1 private_subnet

# Get a Cirrus VM Image that will be used for the test and create Glance Image
export http_proxy=http://"192.168.0.33":"3128"/
export https_proxy=http://"192.168.0.33":"3128"/
yum install -y wget
wget http://download.cirros-cloud.net/0.3.4/cirros-0.3.4-x86_64-disk.img
unset http_proxy
unset https_proxy
glance image-create --name='cirros image' --is-public=true  --container-format=bare --disk-format=qcow2 --file cirros-0.3.4-x86_64-disk.img
# Disable packstack_installation service
rm '/etc/systemd/system/multi-user.target.wants/pacstack_installation.service'
mv -f /etc/systemd/system/pacstack_installation.service /root
EOFPACKSTACK

# Make /root/packstack_install.sh executable
chmod ug+x /root/packstack_install.sh

# Create Systemd Services
cat > /etc/systemd/system/pacstack_installation.service << EOFSYSTEMD
[Unit]
Description=Packstack Automated Installation
After=sshd.service

[Service]
Type=oneshot
ExecStart=/root/packstack_install.sh > /root/packstack_install.log 2>&1
User=root
Group=root

[Install]
WantedBy=multi-user.target
EOFSYSTEMD

# Make sure that Systemd Service will be enabled during the next boot
ln -s '/etc/systemd/system/pacstack_installation.service' '/etc/systemd/system/multi-user.target.wants/pacstack_installation.service'

###Go back to tty1##
exec < /dev/tty1 > /dev/tty1
chvt 1

# End of the %post section
%end

References:

https://www.rdoproject.org/Neutron_with_existing_external_network
http://0pointer.de/blog/projects/changing-roots
http://www.freedesktop.org/software/systemd/man/systemd.service.html

During my last post, I described the redirection of Linux Output to Serial on an Upstart Distribution based (using RHEL6). The main aim of this post is to describe the same on Systemd Distribution based (RHEL7). Before I begin with the technical matters, I have to say that I've been quite impressed by how Systemd makes this configuration so easy (no pain at all! So cool!). This isn't to make a comparison between Systemd and Traditional Init or Upstart, but you can check these two previous posts to draw your own Conclusions: VSP/Traditional Init, VSP/Upstart.

Let's now delve in the interesting matters. The whole procedure is just about setting Kernel Options and reboot, and if the reboot can't be performed right away, just start a systemd service.

1. Set the Kernel Options boot options:

On RHEL7 with Grub2, add "console=ttyS1" to GRUB_CMDLINE_LINUX in /etc/default/grub file (You might also remove rhgb quiet as rhgb is for RedHat Graphical Boot and quiet is meant to hide the majority of boot messages before rhgb starts)

Changes to /etc/default/grub require rebuilding the grub.cfg file. This file location's on BIOS based machine is /boot/grub2 and for UEFI based machine, it is /boot/efi/EFI/redhat/.

On BIOS Based Machine:

On UEFI Based Machine:

2. Reboot or start a serial-getty service on ttyS1

Now we can either reboot the System to have the Kernel Loaded with the new parameter during the reboot , or (especially if we can't afford a downtime :-)) run the following to have a getty service started right away on the ttyS1.

That's it! So simple! Go on the console, run vsp and there's a nice prompt...

Reference:
http://0pointer.de/blog/projects/serial-console.html

Steve's Solaris/Linux experiences

2015/07/29

Packstack Installation with Existing External Network / kickstart RHEL7 (CentOS7)

2014/09/16

HP ILO / RHEL7 Systemd Output to VSP console