It's vznet.conf not vznetctl.conf, see e.g.:
http://git.openvz.org/?p=vzctl;a=blob;f=bin/vznetcfg.in;h=e91f5c4a0744c1e...
---
docs/drvopenvz.html.in | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/docs/drvopenvz.html.in b/docs/drvopenvz.html.in
index bb437d3..a8f9f28 100644
--- a/docs/drvopenvz.html.in
+++ b/docs/drvopenvz.html.in
@@ -67,7 +67,7 @@ openvz+ssh://root@example.com/system (remote access, SSH tunnelled)
script must be created manually by the host OS administrator. The
simplest way is to just download the latest version of this script
from a newer OpenVZ release, or upstream source repository. Then
- a generic configuration file <code>/etc/vz/vznetctl.conf</code>
+ a generic configuration file <code>/etc/vz/vznet.conf</code>
must be created containing
</p>