Requests from back-end server to google cloud load balancer are directed to the origin server

[__jatin_3]

Hello, we have a configuration with a google cloud load balancer(lb) with two back-end servers(a,b). 
'lb' is configured with 'a' and 'b' servers in active-passive mode.
All requests from external servers on 'lb' is directed to the active server 'a'. And 'b' server act as a backup (fail over).

Problem:
Any request generated from back-end servers 'a' or 'b' to 'lb' is directed to the origin server.
Any request from 'b' server to 'lb' is directed to 'b'
Any request from 'a' server to 'lb' is directed to 'a' 

Expectation:
Requests from back-end servers 'a' or 'b' to 'lb' should be directed in active passive mode only.
Any request from 'a' or 'b' server to 'lb' should be directed to 'a' (active server)

[VannGuce]

Hi,

The active/passive is not supported at load balancer, its traffic distribution use a Round Robin wherein the distribution of traffic spreads between instances. You can check the explanation under “Traffic Distribution”[1] of load balancer. Let me also share the comparison of load balancer that use Round Robin[2].

However, there is a failover feature in the external passthrough Network Load balancer that might fit in your set up, you can check this link[3] wherein it explains how failover works in this load balancer. Also sharing how to configure failover[4].

[1]https://cloud.google.com/load-balancing/docs/https#load_distribution_algorithm
[2]https://cloud.google.com/load-balancing/docs/features#load_balancing_methods
[3]https://cloud.google.com/load-balancing/docs/network/networklb-failover-overview
[4]https://cloud.google.com/load-balancing/docs/network/networklb-setting-up-failover#configure_the_loa...

[__jatin_3]

hello,
Thanks for the reply!
The configuration is exactly like what you have suggested. Since we have only two back-ends so, it acts in the active-passive manner.
But the problem statement is different.

We are trying to curl requests from fail-over back-end server to lb AND lb directs the request back to the fail-over server!