VZ configuration

vz_setup

def configure_vzkernel():
    
    def run_in_vz(veid, cmd):
        # Use pty so commands with sudo in them work
        sudo("vzctl exec %s '%s'" % (veid, cmd), pty=True)
    
    log.info("Downloading Centos6 VZ template")
    sudo("wget http://download.openvz.org/template/precreated/centos-6-x86_64.tar.gz")
    sudo("mv centos-6-x86_64.tar.gz /vz/template/cache")
    
    sed("/boot/grub/menu.lst", before='^default=1$', after='default=0', use_sudo=True)
    
    # OpenVZ turns off NAT - need to turn back on - performance bug but we need NAT
    sed("/etc/modprobe.d/openvz.conf", before="ip_conntrack_disable_ve0=1",
        after="ip_conntrack_disable_ve0=0", use_sudo=True)
    
    sudo("shutdown -r now")
    
    # Force Fabric to reconnect instead of caching the connection
    disconnect_all()
    
    log.info("Rebooting into OpenVZ kernel -- sleeping 90 seconds")
    time.sleep(90)
    
    VZ_SUBNET = "192.168.2.0/24"
    host_node_ip = run("curl http://169.254.169.254/latest/meta-data/local-ipv4")
    # Source NAT - 192.168.2.0/24 maps to the HN's private IP
    sudo("iptables -t nat -A POSTROUTING -s %s -o eth0 -j SNAT --to %s"
         % (VZ_SUBNET, host_node_ip))
    
    # OpenVZ bug with ploop? http://en.5.ispdoc.com/index.php/No_space_left_on_device
    sudo("echo 0 > /sys/module/ploop/parameters/root_threshold")
    sudo("echo 0 > /sys/module/ploop/parameters/user_threshold")