When you install multiple engines and virtual proxies, you must add load balancing to the new nodes and virtual proxies. It is only on the central node that load balancing is automatically added. If you create a node without configuring the virtual proxy, the node will never actually be used. If you create a new virtual proxy, you must configure it by adding load balancing and selecting which nodes that the virtual proxy can forward work to.
The default load balancing algorithm, Round robin, evenly distributes the load among the available nodes in a multi-node site. Alternatively, you can choose Memory allocation load balancing, an enhanced version of Round robin that considers engine health data and prioritizes nodes with the most available memory. You can also enable sticky load balancing and engine saturation checks to be used together with the load balancing algorithm. With sticky load balancing enabled, the proxy service attempts to redirect all app open requests to an engine where the app is already open. With engine saturation checks, it monitors engine availability and redirects app open requests to other available engines if an engine becomes saturated.
Same user/client session is determined by the information contained in the following request headers:
Do the following:
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Open the QMC: https://<QPS server name>/qmc
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Select Virtual proxies on the QMC start page or from the Start
drop-down menu to display the overview. -
Select the virtual proxy that you want to add load balancing to.
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Click Edit.
The virtual proxy properties are shown.
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In the Load balancing property, click
Add new server node to select which server nodes to add load balancing to.A dialog opens.
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Select nodes from the list.
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Click Add.
The dialog closes and the nodes are added in the list of Load balancing nodes on the virtual proxy edit page.
A confirmation dialog is displayed.
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In the Load balancing algorithm dropdown, choose Round robin or Memory allocation.
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Optionally, select Sticky load balancing. With this enabled, the proxy service will attempt to redirect all app open requests to an engine where the app is already open.
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Optionally, select Engine saturation check to monitor engine availability during load balancing. If an engine is saturated, the app open requests are redirected to other available engines.
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Click OK.
Successfully updated is displayed at the bottom of the page.