Create the First Data Node

After you Create Monitoring Service, you can create the first data node. The settings that you configure here can be copied to create further nodes in the system.

To create the first data node, you have to perform the following tasks:

Overview

IP Address Numbering

When you create a new node, you assign it an internal number and an external number. These numbers determine the node's IP address on the private and public networks respectively.

  • Node Number: Determines the last octet of the node's IP address on the private network (cluster-internal network). For example, if the node's number is configured as '15', the private IP address is 27.1.0.15.
  • External Number: Determines the last octet of the node's IP address on the public network (client-side network). This is done by adding the External Number assigned to the node to the last octet of the public network address.
Example

Client-Side Network Address + External Number = Client-Side Node IP Address

Public Network Access Network Mask External Number Node IP Address
10.70.0.50 255.255.255.0 (24) 34 10.70.0.84
10.70.0.70 255.255.255.0 (24) 1 10.70.0.71

Distance between Node and External Number

When you enter external numbers for nodes, the distance between the IP addresses of the nodes and the external numbers must be equal. This equal distance is essential when using IMPORT FROM EXA and EXPORT INTO EXA, as there is a requirement to access the IP address when connecting from EXA to the EXA database. For example, consider the table below, you can see that for node n11, the external number is 21, and the distance between them is 10. Likewise, for node n17 the external number is 27, and the distance between them is 10. Suppose, for node n18, the external number is 30(instead of 28); then, the distance would be 12, which his incorrect, and you will receive an exception message.

Node Number External Number
11 21
17 27
18 28
19 29

If the IP address does not match this requirement, you will get the following exception message:

ETL-4212: Parallel connection from <source host> to external EXASolution at <destination host and port> failed. [No server listening.]

Disk Layout

The disk layout for a node is configured during the node setup. For a data node, the following four partitions are required:

  • OS partition (d00_os): EXACluster OS is installed on this partition. It is an ext4 filesystem with journaling, and is AES 256 encrypted. It should be assigned at least 50 GiB of space.
  • Swap partition (d01_swap): Used for swap data. It should be assigned at least 4 GiB of space.
  • Data partition (d02_data): Used for database logs and coredumps. It is an ext4 filesystem with journaling. It should be assigned at least 50 GiB of space.
  • EXAStorage partition (d03_storage): Used for persistent and temporary database data. It is an EXAStorage partition and runs on one or more physical disks.

For a physical cluster, how you set up your disk layout depends on the hardware setup you have selected - a RAID Mirror with a Software RAID, or a hard drive with a dedicated OS disk.

RAID Mirror with Software RAID

All hard drives are the same size, and are used by all partitions (OS, Data, Swap and Storage). You configure the node disks as follows:

  • Add all disks to the OS, Swap, Data and Storage partitions
  • OS, Swap and Data have a disk RAID of 'RAID 0'
  • Storage has a disk RAID of 'None'

Example : RAID mirror with software RAID (Dell R710)

HDD with Dedicated OS Disk

The OS, Swap and Data partitions have a dedicated hard drive. The hard drive for these partitions is usually smaller than the hard drives for the Storage partition. You configure the node disks as follows:

  • Add the dedicated hard drive to the OS, Swap and Data partitions
  • Add all other hard drives to the Storage partition
  • OS, Swap and Data use the dedicated OS disk
  • Storage has a disk RAID of 'None'

Example : HDD with dedicated OS disk (Dell R720XD)

Create a Node

Follow these steps to create/add node(s) to the Exasol system:

  1. In EXAoperation, go to Configuration > Nodes. The Cluster Nodes screen is displayed.
  2. Click Add. The Add EXACluster node screen is displayed.
  3. Configure the details of the node being added. For a full description of each property, refer to Configure Node Properties section.
  4. Click Add to add the node. The new node is listed with the status To Install.

Configuring the Node Disk Layout

You can follow the below steps to configure a node disk layout: 

  1. In EXAoperation, go to Configuration > Nodes and click on the node link.
  2. The Node Information screen is displayed.
  3. Click Disks. The Disk Information screen is displayed.
  4. Click Edit to edit the disk. Configure the following for each partition: 
    • Disk devices: The physical disk(s) that the storage disk runs on. Click Add for each device to add to the partition.
    • Disk RAID: Redundancy of the disk.
    • Disk encryption: Select the encryption to be used for the partition.
    • Disk Label: Name for the partition as it should appear in screens across EXAoperations.
    • Size of disk: The maximum space in GiB available to the partition.

    The way you configure the disks depends on your hardware setup (refer to Disk Layout). You have the following two options:

    RAID Mirror with Software RAID

    PartitionDisk Device to AssignDisk RAIDSize of Disk
    OSAllRAID 050GiB
    SwapAllRAID 04GiB
    DataAllRAID 050 GiB
    Storage AllSelect 'None'Leave blank

    Hard Drive With Dedicated OS Disk

    PartitionDisk Device to AssignDisk RAIDSize of Disk
    OSDedicated HDDSelect 'None'50GiB
    SwapDedicated HDDSelect 'None'4GiB
    DataDedicated HDDSelect 'None'Leave blank
    Storage Dedicated HDDSelect 'None'Leave blank
  5. Click Apply to save your changes.

Install a Node

Follow these steps to install node(s).

  1. In EXAoperation, go to Configuration > Nodes to open the Cluster Nodes screen.
  2. The node you have just added should be displayed as To Install in the State/Op. column. If not, select the node, and select Set Install Flag from the Actions ... drop down list, and click Execute.

  3. Start the node up so that it can complete the installation process. Depending on if you use IPMI or not, you have two options:
  4. Option Steps
    No IPMI installed: start node manually Physically power on the relevant node in the cluster.
    IPMI is installed: start node using EXAoperation
    1. Go to Configuration > Nodes.
    2. Select the new node and select Startup from the Actions ... drop down list.
    3. Click Execute to install the node and start it up
  5. The node is shown as Running in the State/Op. column.

 

Next Step

Create Additional Nodes