diff --git a/controllers/nginx/pkg/cmd/controller/nginx.go b/controllers/nginx/pkg/cmd/controller/nginx.go
index 8e6873c50a..e780d1dd94 100644
--- a/controllers/nginx/pkg/cmd/controller/nginx.go
+++ b/controllers/nginx/pkg/cmd/controller/nginx.go
@@ -25,6 +25,7 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"strconv"
 	"syscall"
 	"time"
 
@@ -364,7 +365,11 @@ func (n *NGINXController) OnUpdate(ingressCfg ingress.Configuration) ([]byte, er
 
 	// the limit of open files is per worker process
 	// and we leave some room to avoid consuming all the FDs available
-	maxOpenFiles := (sysctlFSFileMax() / cfg.WorkerProcesses) - 1024
+	wp, err := strconv.Atoi(cfg.WorkerProcesses)
+	if err != nil {
+		wp = 1
+	}
+	maxOpenFiles := (sysctlFSFileMax() / wp) - 1024
 
 	setHeaders := map[string]string{}
 	if cfg.ProxySetHeaders != "" {
diff --git a/controllers/nginx/pkg/config/config.go b/controllers/nginx/pkg/config/config.go
index 15fa300d3d..aab72dfbd3 100644
--- a/controllers/nginx/pkg/config/config.go
+++ b/controllers/nginx/pkg/config/config.go
@@ -19,6 +19,7 @@ package config
 import (
 	"fmt"
 	"runtime"
+	"strconv"
 
 	"github.com/golang/glog"
 
@@ -252,7 +253,7 @@ type Configuration struct {
 
 	// Defines the number of worker processes. By default auto means number of available CPU cores
 	// http://nginx.org/en/docs/ngx_core_module.html#worker_processes
-	WorkerProcesses int `json:"worker-processes,omitempty"`
+	WorkerProcesses string `json:"worker-processes,omitempty"`
 }
 
 // NewDefault returns the default nginx configuration
@@ -285,7 +286,7 @@ func NewDefault() Configuration {
 		SSLSessionTickets:        true,
 		SSLSessionTimeout:        sslSessionTimeout,
 		UseGzip:                  true,
-		WorkerProcesses:          runtime.NumCPU(),
+		WorkerProcesses:          strconv.Itoa(runtime.NumCPU()),
 		VtsStatusZoneSize:        "10m",
 		UseHTTP2:                 true,
 		Backend: defaults.Backend{