diff --git a/docs/reference/modules/transport.asciidoc b/docs/reference/modules/transport.asciidoc index fc7b6831ca84..b7c0282384e7 100644 --- a/docs/reference/modules/transport.asciidoc +++ b/docs/reference/modules/transport.asciidoc @@ -195,6 +195,15 @@ setting `transport.ping_schedule` if keepalives cannot be configured. Devices which drop connections when they reach a certain age are a common source of problems to {es} clusters, and must not be used. +If an {es} node is temporarily unable to handle network traffic it may stop +reading data from the network and advertise a zero-length TCP window to its +peers so that they pause the transmission of data to the unavailable node. This +is the standard backpressure mechanism built into TCP. When the node becomes +available again, it will resume reading from the network. Configure your +network to permit TCP connections to exist in this paused state without +disruption. Do not impose any limit on the length of time that a connection may +remain in this paused state. + For information about troubleshooting unexpected network disconnections, see <>.