Hello @Nick Paramonov ,
Azure Load Balancer has an idle timeout setting of 4 minutes to 30 minutes. By default, it is set to 4 minutes. And 30 minutes is the maximum available limit of TCP idle timeout at the moment.
Please refer : https://learn.microsoft.com/en-us/azure/load-balancer/load-balancer-tcp-idle-timeout#tcp-idle-timeout
https://feedback.azure.com/forums/217313-networking/suggestions/18823588-increase-idle-timeout-on-internal-load-balancers-t#{toggle_previous_statuses}
If you wish you may leave your feedback here requesting this feature. All the feedback you share in these forums will be monitored and reviewed by the Microsoft engineering teams responsible for building Azure.
However, you can use Standard Load Balancer to enable TCP Reset on Idle for a given rule. Enabling this feature will cause Load Balancer to send bidirectional TCP Resets (TCP RST packet) on idle timeout. This will inform your application endpoints that the connection has timed out and is no longer usable. Endpoints can immediately establish a new connection if needed.
Please refer : https://learn.microsoft.com/en-us/azure/load-balancer/load-balancer-tcp-reset
Kindly let us know if the above helps or you need further assistance on this issue.
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