Configuring Upstream Groups

The Upstream Groups table lets you configure up to 10 Upstream Groups. Once configured, you can configure Upstream Hosts for the Upstream Group (see Configuring Upstream Hosts).

An Upstream Group is a set of one or more hosts (Upstream Host) that can serve a particular set of data. The HTTP Proxy distributes the requests among the members (hosts) of the Upstream Group according to the specified load balancing mode.

The Upstream Group may be made up of one or more primary hosts and zero or more backup hosts. HTTP requests for the Upstream Group are distributed among all the primary hosts. Backup hosts do not receive requests unless all the primary hosts are down.

The following procedure describes how to configure Upstream Groups through the Web interface. You can also configure it through ini file [UpstreamGroup] or CLI (configure network > http-proxy > upstream-group).

To configure an Upstream Group:
1. Enable the HTTP Proxy application, as described in Enabling the HTTP Proxy Application.
2. Open the Upstream Groups table (Setup menu > IP Network tab > HTTP Proxy folder > Upstream Groups).
3. Click New; the following dialog box appears:

4. Configure an Upstream Group according to the parameters described in the table below.
5. Click Apply, and then save your settings to flash memory.

Upstream Groups Table Parameter Descriptions

Parameter

Description

General  

'Index'

[Index]

Defines an index number for the new table row.

Note:

Each row must be configured with a unique index.
The parameter is mandatory.

'Name'

name

[Name]

Defines a descriptive name, which is used when associating the row in other tables.

The valid value is a string of up to 40 characters. By default, no value is defined.

Note:

Configure each row with a unique name.
The NGINX directive for this parameter is "upstream name { … }".
The parameter is mandatory.
The parameter value cannot contain a forward slash (/).

'Protocol'

protocol

[Protocol]

Defines the protocol.

[0] HTTP/HTTPS (default)
[1] TCP/UDP

Note:

To assign the Upstream Group to a TCP/UDP Proxy Server, configure the parameter to TCP/UDP. To configure TCP/UDP Proxy Servers, see Configuring TCP-UDP Proxy Servers.
To assign the Upstream Group to an HTTP Proxy Server, configure the parameter to HTTP/HTTPS. To configure HTTP Proxy Servers, see Configuring HTTP Proxy Servers.
For NGINX, the parameter determines nesting within the "http" or "stream" context.

'Load Balancing Mode'

load-balancing-mode

[LoadBalancingMode]

Defines the load-balancing of traffic method for the hosts belonging to the Upstream Group.

[0] Round Robin = (Default) Traffic requests are balanced across all hosts. Every consecutive request is sent to the next available host.
[1] IP Hash = All requests from a given client (by IP address) is sent to the same host, regardless of current load.
[2] Least Connections = New requests are sent to the host with the fewest active connections.

Note: The NGINX directive for this parameter is "ip-hash (1)", "least-conn (2)", and "round-robin (0)".

'Max Connections'

max-connections

[MaxConnections]

Defines the maximum number of simultaneous active connections to the proxied Upstream Host server. Configuring the parameter to a non-zero value activates connection re-use and limits the number of connections towards the upstream server.

The default is 0, meaning unlimited connections (i.e., a new upstream connection is opened for every incoming HTTP or HTTPS request).

Note: To fully utilize the connection re-use capability, you must also include the following directives at the HTTP Location level:

proxy_http_version 1.1;
proxy_set_header Connection “”;

For more information on adding directives, see Configuring HTTP Directives.