Radiator Server Documentation — v10.34.2

backends.http.keepalive

Table of Contents

keepalive

`keepalive`

Configure TCP keepalive probes for the connections an HTTP backend opens to its service. Probes detect a service or network path that disappeared without closing the connection, so a pooled connection is not reused after it has stopped working. This backend-level setting applies to both a single url and named server endpoints.

backends {
    http "API" {
        url "https://api.example.com";
        keepalive {
            idle 60s;
            interval 10s;
            count 3;
        }
        get "LOOKUP" { path "/users"; }
    }
}

Parameter	Description	Accepted values
`idle`	Time a connection must be idle before probes start	Whole seconds from `1s` to `32767s`
`interval`	Time between individual keepalive probes	Whole seconds from `1s` to `32767s`
`count`	Number of failed probes before connection is closed	`1` to `127`

Set all three parameters in the keepalive block.

Without a keepalive block, HTTP backend connections start probing after 15s idle, send probes every 15s, and close the connection after 3 failed probes.