Read Write CIFS Netapp very slow

Hello,
my simplified config :
One Netapp CIFS & NFS 172.16.255.2
One VM W2008R2 with one network 10.0.20.101
One VyOS 4 eth 20 VIF, VIF20 10.0.20.254 and eth2 172.16.255.254

test tried :
from VM copy file from CIFS (172.16.255.2) to C:/ speet avg 40m/s
from VM copy file from CIFS (172.16.255.2) to CIFS (172.16.255.2) speet avg 100ko/s !!

if I change on VM with IP 172.16.255.100 for bypass Vyos
from VM copy file from CIFS (172.16.255.2) to CIFS (172.16.255.2) speed avg 40Mo/s !!

Could you help me ?
Thx.

can you tell us a bit more about your setup?
Version?
Hardware?
CPU?
RAM?
Networks Interface?
etc.?

I see what you are saying, the read/write performance to a CIFS share is ok if it’s on the same subnet but not if it is routed through the VyOS box you have set up. Along with the pertinant information asked for can you say whether the VyOS instance is a VM or a physical box. Also, if your windows VM only has a single interface on 10.0 network, how does it route to the filer which has a 172.16 address if you don’t put the VyOS router in the middle?