Vnx-rootfslxccentos

How to create a LXC CentOS root filesystem for VNX

Basic installation

Follow this procedure to create a CentOS based LXC root filesystem for VNX. The procedure has been tested with CentOS version 7.

• Create the rootfs with:

sudo apt-get install yum
lxc-create -t centos -n vnx_rootfs_lxc_centos -- -R 7 -a x86_64

• Change root password (e.g. xxxx):

chroot /var/lib/lxc/vnx_rootfs_lxc_centos/rootfs passwd

• Move the rootfs to VNX filesystems directory:

mv /var/lib/lxc/vnx_rootfs_lxc_centos /usr/share/vnx/filesystems/vnx_rootfs_lxc_centos64-7-v025

• Edit the rootfs configuration file (/usr/share/vnx/filesystems/vnx_rootfs_lxc_ubuntu-16.04/config) to reflect the directory change:

lxc.rootfs = /usr/share/vnx/filesystems/vnx_rootfs_lxc_centos64-7-v025/rootfs

• Create fstab file (if not created):

touch vnx_rootfs_lxc_centos64-7-v025/fstab

• Start the new rootfs to configure it and install new software:

lxc-start -n vnx_rootfs_lxc_centos64-7-v025 -F -f /usr/share/vnx/filesystems/vvnx_rootfs_lxc_centos64-7-v025/config

• Once the VM has started, make login (root/xxxx) and add VNX user and change the passwords:

adduser vnx
passwd vnx

• Update and install software:

yum update
yum install perl telnet wget openssh-clients traceroute tcpdump net-tools

• Change VM name in hosts and hostname files:

sudo vi /etc/hosts         # change name to vnx
sudo vi /etc/hostname      #     "

• Add commands to create /dev/kvm and /dev/net/tun devices at startup (/etc/rc.local):

sed -i -e "/exit 0/d" /etc/rc.local
echo "# /dev/net/tun" >> /etc/rc.local
echo "mkdir -p /dev/net/" >> /etc/rc.local
echo "mknod -m 666 /dev/net/tun c 10 200" >> /etc/rc.local
echo "" >> /etc/rc.local
echo "# /dev/kvm" >> /etc/rc.local
echo "mknod -m 660 /dev/kvm c 10 232" >> /etc/rc.local

• Delete command history:

history -c

• Stop the VM with:

halt

• If you want to pack the root filesystem into a tar file, use the following command:

tar --numeric-owner -czpf vnx_rootfs_lxc_centos64-7-v025.tgz vnx_rootfs_lxc_centos64-7-v025

• Optionally, create a short link to the rootfs:

cd /usr/share/vnx/filesystems
ln -s vnx_rootfs_lxc_centos64-7-v025 rootfs_lxc_centos64

References

• Setup Linux Container with LXC on Ubuntu 16.04. http://www.itzgeek.com/how-tos/linux/ubuntu-how-tos/setup-linux-container-with-lxc-on-ubuntu-16-04-14-04.html