Create Load Balancers

In this document you can find information on how to create Load Balancer or Auto-Scaling cluster in your cloud.  

With the Load Balancer clusters option, you specify which VSs (nodes) will participate in a load balancer cluster. Incoming traffic is distributed evenly between all the VSs added to a cluster – you still present a single host name to end users, but they actually access the cluster of VSs rather than a single end point. This helps application availability: if one VS fails, traffic is automatically routed to another in the cluster. You can add and remove cluster VSs as required. 

VS Auto-Scaling clusters increase or decrease your VS capacity by automatically adding or removing nodes to a cluster. The cluster is scaled in (decreased) or out (increased) based on rules you specify in the Control panel. This aids application performance and scalability.

Load Balancers, both autoscaling clusters and load balancer clusters, can only be created on the basis of Virtual Servers, and are not available for Smart Servers, Baremetal Servers, or VMware Virtual Servers.



Create Load Balancer Cluster



In this scheme, load balancers manage incoming requests one by one, rotating them between the servers added to a cluster (a round-robin method). 

OnApp load balancers are based on Layer 4 load balancing which means that requests are distributed at the transport layer, such as TCP or UDP transport protocols. To add an LB cluster:

  1. Go to your Control Panel > Cloud > Load Balancers menu.
  2. Click the Add New Balancer button.
  3. On the page that follows, fill in the form that appears:

Configuration

Cluster Configuration

  • Port - specify the port for this load balancer to run on (e.g. 9090, 8080, 9008 etc.)

To add multiple load balancer ports, click the "+" button next to the first port.


Load Balancer Instance

  • Label – give a name to your load balancer instance.
  • Hostname – specify a host name that will identify your load balancer.
  • Compute zone – choose a Compute zone.
  • Compute resource – select a Compute resource that will be enabled for the cluster.
  • Network zone – choose a network zone for this load balancer.
  • Port Speed – use the slider to set a port speed or tick the Unlimited box if required.
  • CPU Priorityset the load balancer's CPU priority. 


Load Balancer Type

  • Load Balancer Type - choose the Cluster option and click Next.

Cluster Nodes


This is where you add and configure the nodes in this load balancing cluster. A node is a combination of a VS and an IP address.

  • Virtual Server - select a virtual server from the drop-down box and click the Add Node button.

Click Save to create the load balancer cluster.

The only VSs you can add to a cluster are those which are based on the selected Compute resource/Compute zone, have an IP in the defined network zone and are located in the same IP range.

Enabled anti-spoofing would prevent adding Windows-based virtual servers as nodes to the load balancer cluster. To disable anti-spoofing reboot windows-based nodes from Control Panel after they are added to the cluster.



Create Auto-Scaling Cluster



To add an autoscaling cluster to your cloud:

  1. Go to your Control Panel > Cloud > Load Balancers menu.
  2. Click the Add a Balancer button.
    On the page that follows, fill in the form that appears:

Configuration

Cluster Configuration

  • Port - specify the port for this load balancer to run on (e.g. 9090, 8080)


Load Balancer Instance

  • Label – give a name for your load balancer instance.
  • Hostname – specify a host name which will identify your load balancer.
  • Compute zone – choose a Compute zone.
  • Compute resource – select a Compute resource that will be enabled for the cluster.
  • Network zone – choose a network zone for this load balancer.
  • Port Speed – use the slider to set a port speed or tick the Unlimited box if required.
  • CPU Priority - set the load balancer's CPU priority. 


Load Balancer Type

  • Load balancer type - choose the Autoscaling option and click Next.

Cluster Nodes

These settings configure the nodes that will be added to your cluster.


Nodes network 

  • Nodes network group - the nodes network group for the cluster nodes.



Cluster Node Template

  • Image template – choose a template from the drop-down box: nodes will be built on this template.

    The only templates you can add to a cluster are those based on the selected Compute resource/Compute zone.

  • Min node amount – the minimum number of nodes in this cluster.

    Example: if you set Min node amount = 2 and Max node amount = 5, then the system will scale out the cluster up to 5 nodes, and scale in to 2 nodes if required.

  • Max node amount – the maximum number of nodes in this cluster.


Cluster Node Parameters
These are the settings for each node of a cluster. Each node added to a cluster will have the following parameters:


  • Memory – set the amount of memory allocated per node in MB.
  • CPUs – the number CPUs which will form each node.
  • Rate Limit – set the port speed for a node.

Autoscale Out Parameters
Set the rules defining when the system should add more nodes to your autoscaling cluster. The system will add nodes until the limit set in the Max node amount field is reached.

Autoscale In Parameters
Set the rules defining when the system should remove the nodes from your autoscaling cluster. The system will remove nodes until the limit set in the Min node amount field is reached.

Click Save to create the autoscaling cluster.