diff --git a/README.md b/README.md
index 4390cabad..1b6db3521 100644
--- a/README.md
+++ b/README.md
@@ -204,10 +204,8 @@ Do not forget substituting `<victoriametrics-addr>` with the real address where
 
 VictoriaMetrics maps Influx data using the following rules:
 * [`db` query arg](https://docs.influxdata.com/influxdb/v1.7/tools/api/#write-http-endpoint) is mapped into `db` label value.
-* Field names are mapped to time series names prefixed with `{measurement}{separator}` value.
-  `{separator}` equals to `.` by default, but can be changed with `-influxMeasurementFieldSeparator` command-line flag.
-  It is recommended setting it to `_` in order to be compatible with Prometheus, Promxy and `prometheus_client` plugin for Telegraf.
-  See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/79) for details.
+* Field names are mapped to time series names prefixed with `{measurement}{separator}` value,
+  where `{separator}` equals to `_` by default. It can be changed with `-influxMeasurementFieldSeparator` command-line flag.
   See also `-influxSkipSingleField` command-line flag.
 * Field values are mapped to time series values.
 * Tags are mapped to Prometheus labels as-is.
diff --git a/app/vminsert/influx/request_handler.go b/app/vminsert/influx/request_handler.go
index c077ad652..7911e2124 100644
--- a/app/vminsert/influx/request_handler.go
+++ b/app/vminsert/influx/request_handler.go
@@ -18,7 +18,7 @@ import (
 )
 
 var (
-	measurementFieldSeparator = flag.String("influxMeasurementFieldSeparator", ".", "Separator for `{measurement}{separator}{field_name}` metric name when inserted via Influx line protocol")
+	measurementFieldSeparator = flag.String("influxMeasurementFieldSeparator", "_", "Separator for `{measurement}{separator}{field_name}` metric name when inserted via Influx line protocol")
 	skipSingleField           = flag.Bool("influxSkipSingleField", false, "Uses `{measurement}` instead of `{measurement}{separator}{field_name}` for metic name if Influx line contains only a single field")
 )