diff --git a/Dockerfile b/Dockerfile
index 53f513e..334c8c7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,6 +7,8 @@ ENV FTP_ROOT /ftp-home
 ENV FTP_USER ftp
 ENV FTP_PASS ftp
 ENV FTP_PORT 21
+ENV FTP_MAX_CONNECTIONS 256
+ENV FTP_MAX_CONNECTIONS_PER_IP 50
 
 VOLUME /ftp-home
 
diff --git a/image/root/bin/simple-ftp-server b/image/root/bin/simple-ftp-server
index dc82765..0238d2f 100755
--- a/image/root/bin/simple-ftp-server
+++ b/image/root/bin/simple-ftp-server
@@ -37,7 +37,7 @@ def main():
     server = FTPServer(address, handler)
 
     # set a limit for connections
-    server.max_cons = 256
+    server.max_cons = int(environ.get('FTP_MAX_CONNECTIONS', '256'))
     server.max_cons_per_ip = int(environ.get('FTP_MAX_CONS_PER_IP', '50'))
 
     # start ftp server