Synnefo » ./kamaki

Creating Servers (Virtual Machines)

===================================

A `server` (also known as `virtual machine`), is created based on a registered

`image` and a preconfigured hardware setup (also known as `flavor`).

Create a virtual server

-----------------------

List available flavors

.. code-block:: console

    [kamaki]: flavor list -l

    1 C1R128D1drbd

        SNF:disk_template: drbd

        disk:              1

        id:                1

        links:

                href: https://example.com/cyclades/compute/v2.0/flavors/1

                rel:  bookmark

                . . . . . . .

                href: https://example.com/cyclades/compute/v2.0/flavors/1

                rel:  self

        name:              C1R128D1drbd

        ram:               128

        vcpus:             1

    2 C1R128D1plain

        SNF:disk_template: plain

        disk:              1

        id:                2

        links:

                href: https://example.com/cyclades/compute/v2.0/flavors/2

                rel:  bookmark

                . . . . . . .

                href: https://example.com/cyclades/compute/v2.0/flavors/2

                rel:  self

        name:             C1R128D1plain

        ram:              128

        vcpus:            1

    [kamaki]:

List available images

.. code-block:: console

    [kamaki]: image compute list

    f1r57-1m4g3-1d Debian Base Alpha

    53c0nd-1m4g3-1d Beta Debian Base

    [kamaki]:

Let's pick the `C1R128D1drbd` (id: 1) flavor and the `Debian Base Alpha` (id:

f1r57-1m4g3-1d) image to create a new virtual server called 'My First Server'

.. code-block:: console

    [kamaki]: server create 'My First Server' 1 f1r57-1m4g3-1d

    accessIPv4:

    accessIPv6:

    addresses:

    adminPass:       Y0uW0nt5eeMeAg4in

    attachments:

    config_drive:

    created:         2013-06-19T12:34:47.362078+00:00

    diagnostics:

    flavor:

            id:    1

    hostId:

    id:              141

    image:

            id:    f1r57-1m4g3-1d

    key_name:        None

    metadata:

                   os:    debian

                   users: root

    name:            My First Server

    progress:        0

    security_groups:

                      name: default

    status:          BUILD

    suspended:       False

    tenant_id:       s0m3-u53r-1d

    updated:         2013-06-19T12:34:48.512867+00:00

    user_id:         s0m3-u53r-1d

    [kamaki]:

.. note:: The adminPass field is not stored anywhere, therefore users would

    rather write it down and change it the first time they use the virtual server

Wait for the virtual server with id 141 to build (optional)

.. code-block:: console

    [kamaki]: server wait 141

    <bar showing build progress, until 100%>

    Server 141 is now in ACTIVE mode

    [kamaki]:

Destroy the virtual server (wait is still optional)

.. code-block:: console

    [kamaki]: server delete 141

    [kamaki]: server wait 141 ACTIVE

    <bar showing destruction progress, until 100%>

    Server 141 is now in DELETED mode

    [kamaki]:

Inject ssh keys to a debian server

----------------------------------

Assume that the servers build from the image `Debian Base Alpha` accept ssh

connections. We need to build servers that can log us as root without a

password. This can be achieved if the `/root/.ssh/authorized_keys` file exists

and contains the public key of the current user.

Assume that the public key file of the current user is located at

`/home/someuser/.ssh/id_rsa.pub` . We need a method of injecting this file as

`/root/.ssh/authorized_keys` while creating the virtual server.

Luckily, Synnefo fully supports the OpenStack suggestion for file injections on

virtual servers and kamaki allows it by using the **-p** argument (p stands for

`PERSONALITY` and is the term used in the

`respective OpenStack <http://docs.openstack.org/api/openstack-compute/2/content/CreateServers.html>`_ description).

The syntax of the -p argument is something called "the personlity string"::

    -p <local file path>[,<remote path>[,<remote owner>[,<remote group>[,<mode>]]]]

    e.g.,

    -p /home/someuser/.ssh/id_rsa.pub,/root/.ssh/authorized_keys,root,root,0777

.. note:: In case of omitting an optional part of the personality string, the

    default behavior depends on the remote server, e.g., for a debian image we

    expect the file to have root ownership, if the ownership is not specified.

Create a virtual server while injecting current user public key to root account

.. code-block:: console

    [kamaki]: server

    [server]: create 'NoPassword Server' 1 f1r57-1m4g3-1d -p /home/someuser/.ssh/id_rsa.pub,/root/.ssh/authorized_keys

    accessIPv4:

    accessIPv6:

    addresses:

    adminPass:       Th1s1s4U5elessTh1ngN0w

    attachments:

    config_drive:

    created:         2013-06-19T12:34:47.362078+00:00

    diagnostics:

    flavor:

            id:    1

    hostId:

    id:              142

    image:

            id:     f1r57-1m4g3-1d

    key_name:        None

    metadata:

                    os:    debian

                    users: root

    name:           No Password Server

    progress:        0

    security_groups:

                    name: default

    status:          BUILD

    suspended:       False

    tenant_id:       s0m3-u53r-1d

    updated:         2013-06-19T12:34:48.512867+00:00

    user_id:         s0m3-u53r-1d

    [server]:

When the virtual server is ready, get the virtual servers external IP from the web UI. Let's assume the

IP is 123.456.78.90 .

.. code-block:: console

    [server]: /exit

    $ ssh 123.456.78.90

    Linux remote-virtual server-4241 2.6.32-5-amd64 #1 SMP XXXX x86_64

    The programs included with the Debian GNU/Linux system are free software;

    the exact distribution terms for each program are described in the

    individual files in /usr/share/doc/*/copyright.

    Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent

    permitted by applicable law.

    root@remote-virtual server-4241:~# ls -l .ssh/

    total 4

    -rw-r--r-- 1 root root 399 Jun 19 12:34 authorized_keys

    root@remote-virtual server-4241:~#

You can now log to your remote virtual server as root, without a password. Well done!

.. note:: There is no reason to limit injections to ssh keys. Users with an

    adequate understanding of the remote OS are encouraged to prepare and

    inject all kinds of useful files, e.g., **lists of package sources**,

    **default user profiles**, **device mount configurations**, etc.

Clusters of virtual servers

---------------------------

A cluster of virtual servers can be created and deleted using special

arguments.

A convention is necessary: all servers belonging to the same cluster will have

names with a common prefix e.g., *cluster1*, *cluster2*, etc. This prefix

acts as the cluster name or the cluster key. Still, users must be careful not to

confuse cluster servers with other servers that coincidentally have the same

prefix (e.g., *cluster_of_stars*).

First, let's create a cluster of 4 servers. Each server will run the image with

id *f1r57-1m4g3-1d* on the hardware specified by the flavor with id *1*. The

prefix of the cluster will be "my cluster "

.. code-block:: console

    $ kamaki

    [kamaki]: server

    [server]: create "my cluster " 1 f1r57-1m4g3-1d --cluster-size=4 --wait

    ... <omitted for clarity>

    adminPass:       S0mePassw0rd0n3

    created:         2013-06-19T12:34:49.362078+00:00

    flavor:

            id:    1

    id:              322

    image:

            id:    f1r57-1m4g3-1d

    name:            my cluster 1

    [progress bar waiting server to build]

    Server 321: status is now ACTIVE

    ... <omitted for clarity>

    adminPass:       S0mePassw0rdTwo

    created:         2013-06-19T12:34:47.362078+00:00

    flavor:

            id:    1

    id:              321

    image:

            id:    f1r57-1m4g3-1d

    name:            my cluster 2

    [progress bar waiting server to build]

    Server 322: status is now ACTIVE

    ... <omitted for clarity>

    adminPass:       S0mePassw0rdThree

    created:         2013-06-19T12:34:55.362078+00:00

    flavor:

            id:    1

    id:              323

    image:

            id:    f1r57-1m4g3-1d

    name:            my cluster 3

    [progress bar waiting server to build]

    Server 323: status is now ACTIVE

    ... <omitted for clarity>

    adminPass:       S0mePassw0rdFour

    created:         2013-06-19T12:34:59.362078+00:00

    flavor:

            id:    1

    id:              324

    image:

            id:    f1r57-1m4g3-1d

    name:            my cluster 4

    [progress bar waiting server to build]

    Server 324: status is now ACTIVE

.. note:: The creation dates are similar but not ordered. This is because the

    servers are created asynchronously. To deactivate asynchronous operations

    in kamaki, set max_theads to 1

    .. code-block:: console

        # Deactivate multithreading

        [server]: /config set max_theads 1

.. note:: the *- - wait* argument is optional, but if not used, the *create*

    call will terminate as long as the servers are spawned, even if they are

    not built yet.

.. warning:: The server details (password, etc.) are printed in

    **standard output** while the progress bar and notification messages are

    printed in **standard error**

Now, let's see our clusters:

.. code-block:: console

    [server]: list --name-prefix "my cluster "

    321 my cluster 2

    322 my cluster 1

    323 my cluster 3

    324 my cluster 4

For demonstration purposes, let's suppose that the maximum resource limit is

reached if we create 2 more servers. We will attempt to expand "my cluster" by

4 servers, expecting kamaki to raise a quota-related error.

.. code-block:: console

    $ kamaki

    [kamaki]: server

    [server]: create "my cluster " 1 f1r57-1m4g3-1d --cluster-size=4 --wait

    Failed to build 4 servers

    Found 2 matching servers:

    325 my cluster 1

    326 my cluster 2

    Check if any of these servers should be removed

    (413) REQUEST ENTITY TOO LARGE overLimit (Resource Limit Exceeded for your

    account.)

    |  Limit for resource 'Virtual Machine' exceeded for your account.

    Available: 0, Requested: 1

The cluster expansion has failed, but 2 of the attempted 4 servers are being

created right now. It's up to the users judgment to destroy them or keep them.

First, we need to list all servers:

.. code-block:: console

    [server] list --name-prefix="my cluster "

    321 my cluster 2

    322 my cluster 1

    323 my cluster 3

    324 my cluster 4

    325 my cluster 1

    326 my cluster 2

.. warning:: Kamaki will always create clusters by attaching an increment at

    the right of the prefix. The increments always start from 1.

Now, our cluster seems messed up. Let's destroy it and rebuilt it.

.. code-block:: console

    [server]: delete --cluster "my cluster " --wait

    [progress bar waiting server to be deleted]

    Server 321: status is now DELETED

    [progress bar waiting server to be deleted]

    Server 322: status is now DELETED

    [progress bar waiting server to be deleted]

    Server 323: status is now DELETED

    [progress bar waiting server to be deleted]

    Server 324: status is now DELETED

    [progress bar waiting server to be deleted]

    Server 325: status is now DELETED

    [progress bar waiting server to be deleted]

    Server 326: status is now DELETED

.. note:: *delete* performs a single deletion if feeded with a server id, but

    it performs a mass deletion, based on the name, if called with --cluster

While creating the first cluster, we had to note down all passwords 

The passwords for each server are printed on the console while creating them.

It would be far more convenient, though, if we could massively inject an ssh

key into all of them. Let's do that!

.. code-block:: console

    [server]: create "my new cluster " 1 f1r57-1m4g3-1d --cluster-size=4 --wait --personality /home/someuser/.ssh/id_rsa.pub,/root/.ssh/authorized_keys,root,root,0777

    ... <output omitted for clarity>

Now, let's check if the cluster has been created.

.. code-block:: console

    [server]: list --name-prefix="my new cluster "

    321 my new cluster 1

    322 my new cluster 2

    323 my new cluster 3

    324 my new cluster 4

We now have a cluster of 4 virtual servers and we can ssh in all of them

without a password.

Here is a bash script for creating clusters:

.. code-block:: bash

    #!/bin/bash

    CL_PREFIX="cluster"

    CL_SIZE=4

    PUB_KEYS="${HOME}/.ssh/id_rsa.pub"

    OUT="cl_servers.txt"

    CLOUD=`kamaki config get default_cloud`

    FLAVOR_ID=1

    IMAGE_ID="f1r57-1m4g3-1d"

    echo "Clean up cluster \"${CL_PREFIX}\""

    kamaki --cloud=${CLOUD} server delete --cluster ${CL_PREFIX} --wait

    echo "Cluster \"${CL_PREFIX}\"" > ${OUT}

    echo "Create cluster \"${CL_PREFIX}\" of size ${CL_SIZE}"

    kamaki --cloud=${CLOUD} server create ${CL_PREFIX} ${FLAVOR_ID} ${IMAGE_ID}

        --cluster-size=${CL_SIZE} --wait

        --personality ${PUB_KEYS},/root/.ssh/authorized_keys,root,root >>${OUT}

    echo "A list of created servers can be found at ${OUT}"