Synnefo » snf-ganeti

NIC slot called ``network``, a new ``Network`` configuration object

(cluster level) and logic to perform IP address pool management, i.e.

maintain a set of available and occupied IP addresses.

Each network will be connected to any number of node groups. During the

connection of a network to a nodegroup, we define the corresponding

connectivity mode (bridged or routed) and the host interface (br100 or

routing_table_200). This is achieved by adding a ``networks`` slot to

the NodeGroup object and using the networks' UUIDs as keys. The value

for each key is a dictionary containing the network's ``mode`` and

``link`` (netparams). Every NIC assigned to the network will eventually

inherit the network's netparams, as its nicparams.

New NIC parameter: network

++++++++++++++++++++++++++

compatibility with the current networking model, a new NIC parameter is

introduced, called ``network`` to reflect the fact that the given NIC

belongs to the given network and its configuration is managed by Ganeti

itself. To keep backwards compatibility, existing code is executed if

the ``network`` value is 'none' or omitted during NIC creation. If we

want our NIC to be assigned to a network, then only the ip (optional)

and the network parameters should be passed. Mode and link are inherited

from the network-nodegroup mapping configuration (netparams). This

provides the desired abstraction between the VM's network and the

node-specific underlying infrastructure.

for NICs belonging to a network. A NIC's IP address can also be

specified manually, as long as it is contained in the network the NIC

Introduce new hooks concerning network operations:

``OP_NETWORK_REMOVE``

  Remove a network from Ganeti

  :directory: network-remove

  :pre-execution: master node

  :post-execution: master node

``OP_NETWORK_SET_PARAMS``

  Modify a network

  :directory: network-modify

  :pre-execution: master node

  :post-execution: master node

For connect/disconnect operations use existing:

``OP_GROUP_SET_PARAMS``

  Modify a nodegroup

  :directory: group-modify

  :pre-execution: master node

  :post-execution: master node

During instance related operations:

During network related operations:

``NETWORK_NAME``

  The friendly name of the network

``NETWORK_SUBNET``

  The ip range of the network

``NETWORK_GATEWAY``

  The gateway of the network

During nodegroup related operations:

``GROUP_NETWORK``

  The friendly name of the network

``GROUP_NETWORK_MODE``

  The mode (bridged or routed) of the netparams

``GROUP_NETWORK_LINK``

  The link of the netparams

To keep the hypervisor-visible changes to a minimum, and maintain

compatibility with the existing network configuration scripts, the

instance's hypervisor configuration will have host-level mode and link

replaced by the *connectivity mode* and *host interface* (netparams) of

the given network on the current node group.

Network configuration scripts detect if a NIC is assigned to a Network

by the presence of the new environment variable:

Conflicting IPs

+++++++++++++++

To ensure IP uniqueness inside a nodegroup, we introduce the term

``conflicting ips``. Conflicting IPs occur: (a) when creating a

networkless NIC with IP contained in a network already connected to the

instance's nodegroup  (b) when connecting/disconnecting a network

to/from a nodegroup and at the same time instances with IPs inside the

network's range still exist. Conflicting IPs produce prereq errors.

Handling of conflicting IP with --force option:

For case (a) reserve the IP and assign the NIC to the Network.

For case (b) during connect same as (a), during disconnect release IP and

reset NIC's network parameter to None

 gnt-network add --network=192.168.100.0/28 --gateway=192.168.100.1 \

                 --network6=2001:db8:2ffc::/64 --gateway6=2001:db8:2ffc::1 \

                 --reserved-ips=192.168.100.10,192.168.100.11 net100

  (Checks for already exising name and valid IP values)

 gnt-network remove network_name

  (Checks if not connected to any nodegroup)

 gnt-network modify --gateway=192.168.100.5 net100

  (Changes the gateway only if ip is available)

 gnt-network modify --reserved-ips=192.168.100.11 net100

  (Toggles externally reserved ip)

 gnt-network connect net100 nodegroup1 bridged br100

  (Checks for existing bridge among nodegroup)

 gnt-network connect net100 nodegroup2 routed rt_table

  (Checks for conflicting IPs)

 gnt-network disconnect net101 nodegroup1

  (Checks for conflicting IPs)

 Network      Subnet           Gateway       NodeGroups GroupList

 net100       192.168.100.0/28 192.168.100.1          1 default(bridged, br100)

 net101       192.168.101.0/28 192.168.101.1          1 default(routed, rt_tab)

 gnt-network info testnet1

 Network name: testnet1

  subnet: 192.168.100.0/28

  gateway: 192.168.100.1

  size: 16

  free: 10 (62.50%)

  usage map:

        0 XXXXX..........X                                                 63

          (X) used    (.) free

  externally reserved IPs:

    192.168.100.0, 192.168.100.1, 192.168.100.15

  connected to node groups:

    default(bridged, br100)

  used by 3 instances:

    test1 : 0:192.168.100.4

    test2 : 0:192.168.100.2

    test3 : 0:192.168.100.3