14.2. Managing Balancing Pools¶
To see a list of balancing pools in a load balancer, click its name.
You can open the pool right pane to monitor its performance and health on the Overview tab, see its parameters on the Properties tab, and manage its members on the Members tab.
Limitations:
The forwarding rule and protocol cannot be changed after the load balancer pool is added.
Prerequisites:
All VMs that will be added in balancing pools have fixed IP addresses.
14.2.1. Add Another Balancing Pool to Load Balancer¶
Click the load balancer name, and then clikc Create balancing pool.
In the Forwarding rule section, select a forwarding rule from the load balancer to the backend protocol, and then specify the ports for incoming and destination connections.
Note the following:
With the HTTPS -> HTTPS rule, all virtual machines need to have the same SSL certificate (or a certificate chain).
With the HTTPS -> HTTP rule, you need to upload an SSL certificate (or a certificate chain) in the PEM format and a private key in the PEM format.
In the Balancing settings section, select the balancing algorithm:
Least connections. Requests will be forwarded to the VM with the least number of active connections.
Round robin. All VMs will receive requests in the round-robin manner.
Source IP. Requests from a unique source IP address will be directed to the same VM.
Enable/disable the Sticky session option to enable/disable session persistence. The load balancer will generate a cookie that will be inserted into each response. The cookie will be used to send future requests to the same VM.
Note
This option is not available in the SSL passthrough mode.
In the Members section, add members, that is, virtual machines, to the balancing pool by clicking Add. Each VM can be included to multiple balancing pools.
In the Add members window that opens, select the desired VMs, and then click Add.
Note
You can select only between VMs that are connected to the chosen network.
In the Health monitor section, select the protocol that will be used for monitoring members availability:
HTTP/HTTPS. The HTTP/HTTPS method GET will be used to check for the response status code 200. Additionally, specify the URL path to the health monitor.
TCP/UDP. The health monitor will check the TCP/UDP connection on the backend port.
PING. The health monitor will check members’ IP addresses.
By default, the health monitor removes a member from a balancing pool if it fails three consecutive health checks of five-second intervals. When a member returns to operation and responds successfully to three consecutive health checks, it is added to the pool again. You can manually set the health monitor parameters, such as the interval after which VM health is checked, the time after which the monitor times out, healthy and unhealthy thresholds. To change the default parameters, click Edit parameters, enter the desired values, and then click Save.
Click Create.
The newly added pool will appear in the list of balancing pools.
14.2.2. Editing Balancing Pool¶
To edit the balancing settings such as the balancing algorithm and session persistence, click the ellipsis icon next to a pool, and then click Edit.
To edit the health monitor parameters, click the ellipsis icon next to a pool, and then click Edit health monitor.
14.2.3. Addinng More Mmbers to Balancing Pool¶
Click the ellipsis icon next to the required balancing pool, and then click + Add members.
In the Add members window, select virtual machines to be added to the balancing pool, and then click Add.
14.2.4. Removing Balancing Pool¶
Click the ellipsis icon next to the required balancing pool, and then click Delete.
Click Delete in the confirmation window.