The staging host will form the base of your operation for creating your cluster. The primary role of the staging host is to hold the Tungsten Replication™ software, and to install, transfer, and initiate the Tungsten Replication™ service on each of the nodes within the cluster. The staging host can be a separate machine, or a machine that will be part of the cluster.
The recommended way to use Tungsten Replication™ is to configure SSH on each machine within the cluster and allow the tpm tool to connect and perform the necessary installation and setup operations to create your cluster environment, as shown in Figure B.1, “Tungsten Deployment”.
The staging host will be responsible for pushing and configuring each machine. For this to operate correctly, you should configure SSH on the staging server and each host within the cluster with a common SSH key. This will allow both the staging server, and each host within the cluster to communicate with each other.
You can use an existing login as the base for your staging operations. For
the purposes of this guide, we will create a unique user,
tungsten, from which the staging
process will be executed.
Create a new Tungsten user that will be used to manage and install
Tungsten Replication™. The recommended choice for MySQL installations is
to create a new user,
You will need to create this user on each host in the cluster. You can
create the new user using
sudo adduser tungsten
You can add the user to the
group adding the command-line option:
sudo usermod -G mysql -a tungsten
Login as the
su - tungsten
Create an SSH key file, but do not configure a password:
ssh-keygen -t rsaGenerating public/private rsa key pair. Enter file in which to save the key (/home/tungsten/.ssh/id_rsa): Created directory '/home/tungsten/.ssh'. Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/tungsten/.ssh/id_rsa. Your public key has been saved in /home/tungsten/.ssh/id_rsa.pub. The key fingerprint is: e3:fa:e9:7a:9d:d9:3d:81:36:63:85:cb:a6:f8:41:3b tungsten@staging The key's randomart image is: +--[ RSA 2048]----+ | | | | | . | | . . | | S .. + | | . o .X . | | .oEO + . | | .o.=o. o | | o=+.. . | +-----------------+
This creates both a public and private keyfile; the public keyfile will be shared with the hosts in the cluster to allow hosts to connect to each other.
Within the staging server, profiles for the different cluster
configurations are stored within a single directory. You can simplify
the management of these different services by configuring a specific
directory where these configurations will be stored. To set the
directory, specify the directory within the
$CONTINUENT_PROFILES environment variable, adding this
variable to your shell startup script
.bashrc, for example) within
your staging server.
mkdir -p /opt/continuent/software/confshell>
mkdir -p /opt/continuent/software/replicator.confshell>
We now have a staging server setup, an SSH keypair for our login information, and are ready to start setting up each host within the cluster.