Adding Clients

This page describes how to add clients to a bare metal cluster.

About Client Hosts

Client hosts are used to run applications which need to access the WekaIO filesystems. They are similar to backend hosts, except that they do not contribute CPUs or drives to the cluster. Consequently, they are only connected to the cluster to use its filesystems.

To add client hosts to the WekaIO system configuration, use the stages described below.

Note: The steps described below represent the traditional approach for mounting a filesystem. However, filesystems can also be mounted using the Stateless Clients feature, which simplifies and improves the management of clients in the cluster and eliminates the process described below. For more information, refer to Mounting Filesystems Using the Stateless Clients Feature.

Stage 1: Install the Software

Verify that the WekaIO software is installed on the client host according to the installation instructions. For further information, see Obtaining the WekaIO Install File and Stage 1 in WekaIO System Installation Process.

Note: All hosts, clients and backends in a WekaIO system cluster must use the same software version. If attempts are made to mix multiple versions, the new hosts will fail to join the cluster.

Stage 2: Joining the Cluster

Command: cluster host add

Once the client host is in the stem mode (this is the mode defined immediately after running the install.shcommand), use the following command line on the client host to add it to the cluster:

weka -H <backend-hostname> cluster host add <client-hostname>

Parameters in Command Line

Name

Type

Value

Limitations

Mandatory

Default

backend-hostname

String

IP/host name of one of the existing backend instances in the cluster

Valid host name (FQDN or IP)

Yes

client-hostname

String

IP/host name of the client currently being added

Valid host name (FQDN or IP)

Yes

Note: On completion of this stage, the host-ID of the newly added host will be received. Make a note of it for the next steps.

Stage 3: Configuring the Host as Client

Command: weka cluster host cores

To configure the new host as a client, run the following command:

weka cluster host cores <host-id> 1 --frontend-dedicated-cores=1

Parameters in Command Line

Name

Type

Value

Limitations

Mandatory

Default

host-id

String

Identifier of host to be added to the cluster

Must be a valid host identifier

Yes

Stage 4: Configuring Client Networking

Command: weka cluster host net add

Note: If the new client is to communicate with the WekaIO system cluster over the kernel UDP stack, it is not necessary to run this command.

If a high-performance client is required and the appropriate network NIC is available, use the following command to configure the networking interface used by the client to communicate with the WekaIO system cluster hosts:

weka cluster host net add <host-id> --device=<net-device> --ips=<ip-address> --netmask=<netmask> --gateway=<gateway>

Parameters in Command Line

Name

Type

Value

Limitations

Mandatory

Default

host-id

String

Identifier of host to be added to the cluster

Must be a valid host identifier

Yes

net-device

String

Network interface device name e.g., eth1

Must be a valid network device name

Yes

ip-address

IP address

IP address of the new interface

Must be a valid IP address

Yes

gateway

IP address

IP address of the default routing gateway

Gateway must reside within the same IP network of ip-address (as described by netmask).

Not relevant for IB / L2 non-routable networks.

No

netmask

Number

Number of bits in the net mask, e.g., the net mask of 255.255.0.0 has 16 netmask bits

Describes the number of bits that identify a network ID (also known as CIDR).

No

Note: When configuring an InfiniBand client, do not pass the --ips, --netmask and --gateway parameters.

Note: InfiniBand clients can only join a cluster with InfiniBand backends. It is not possible to mix InfiniBand and Ethernet clients/backends.

Stage 5: Activating the Host

Command: weka cluster host activate

After successfully configuring the host and its network device, run the following command to finalize the configuration by activating the host:

weka cluster host activate <host-id>

Parameters in Command Line

Name

Type

Value

Limitations

Mandatory

Default

host-id

Comma-separated string

Identifier of host to be added to the cluster

Must be a valid host identifier

Yes