varnish backend VCC-compiler failed - reverse-proxy

Question

i want to add an varnish proxy infront of my SX server i have two droplets ip:192.168.0.100 ip: 192.168.0.101 both works in lan but while restarting varnish shows a compile error
nano /etc/varnish/default.vcl
# define our first nginx server
backend nginx01 {
.host = "192.168.0.100";
.port = "80";
}
# define our second nginx server
backend nginx02 {
.host = "192.168.0.101";
.port = "80";
}
# configure the load balancer
director nginx round-robin {
{ .backend = nginx01; }
{ .backend = nginx02; }
}
# When a request is made set the backend to the round-robin director named nginx
sub vcl_recv {
set req.backend = nginx;
}
while restarting varnish shows an error
root#Sproxy:~# service varnish restart
Message from VCC-compiler:
directors are now in directors VMOD.
('input' Line 30 Pos 1)
director nginx round-robin {
########--------------------
Running VCC-compiler failed, exited with 2
VCL compilation failed
* Syntax check failed, not restarting

Answer 1

Despite the example given by #Redithion, the right configuration for Varnish 4.0 seems to be :
vcl 4.0;
import directors;
backend nginx01 {
.host = "192.168.0.100";
.port = "80";
}
backend nginx02 {
.host = "192.168.0.101";
.port = "80";
}
sub vcl_init {
new nginx = directors.round_robin();
nginx.add_backend(nginx01);
nginx.add_backend(nginx02);
}
sub vcl_recv {
set req.backend_hint = nginx.backend();
}

Answer 2

It seems you are using Varnish 4.0. In this version directors has been moved to VMODs
Here is an example based in what I got from here:
vcl 4.0;
# define first nginx server
backend nginx01 {
.host = "192.168.0.100";
.port = "80";
}
# define second nginx server
backend nginx02 {
.host = "192.168.0.101";
.port = "80";
}
sub vcl_init {
new cluster1 = directors.round_robin();
cluster1.add_backend(nginx01, 1.0);
cluster1.add_backend(nginx02, 1.0);
}
sub vcl_recv {
set req.backend_hint = cluster1.backend();
}
Tip: Don't forget the "vcl 4.0;" statement!