Hi, If I recall correctly, NDIS 5 support was dropped in Windows 8 or early Windows 10. Tap-windows uses NDIS 5, so it almost certainly does not work on Windows Server 2016.
-- Samuli Seppänen Community Manager OpenVPN Technologies, Inc irc freenode net: mattock Il 24/10/18 15:09, tincanteksup ha scritto: > Hi, > > a completely different approach .. > > On the Forum somebody claimed that the old Tap Adaptor works better > than the new one on W2012r2. > > https://forums.openvpn.net/viewtopic.php?f=6&t=27288#p81973 > > Could you test that ? > > Thanks > tct > > > On 03/10/2018 16:15, Rostyslav Maryliak wrote: >> Dear OpenVPN developers, >> >> I've faced a very strange issue with slow outbound network speed from >> Windows Server 2016 Standard server via the OpenVPN tunnel. >> OpenVPN server is Windows Server 2012 R2, client is Windows Server 2016. >> The inbound network speed for Windows Server 2016 is great. >> But the outbound network speed is nearly 30-40 kbps. I've got the same >> results using several tests: iperf testings, file download via SMB, >> Web-based downloading (using HTTP) etc. >> >> The tunnels is getting up and it works greatly, but only in one >> direction - >> from Windows Server 2012 R2 to Windows Server 2016. >> I've been using such server-client configurations setup for several years >> with Windows Server 2012 R2 servers and I've never faced such issue >> before. >> At first I thought that our ISP has some network limitations, but it >> turned >> out that the same tests shows great network speed results using the >> public >> IP addresses in both directions. >> The issue only occurs inside the VPN tunnel. I've spent 3 days tryng to >> figure it out, but failed. I've installed all latest Windows updates, >> reinstalled OpenVPN, tried to switch from UDP to TCP, >> played with performance settings in configs (link-mtu, sndbuf, rcvbuf >> etc) >> but still no luck. I've tested the same setup between two Windows Server >> 2012 R2 servers and it works greatly in both directions. >> Then I've tested it with another Windows Server 2016 Standard server >> (different server and different ISP) and it showed the same awful results >> in outbound direction. >> When I've set the same OpenVPN tunnel between two Windows Server 2016 >> Standard servers I've got the same poor network speed in both directions. >> >> I believe that the issue is somehow related only to the Windows Server >> 2016 >> version and I am more than confident that it depends on server's TCP >> stack >> settings. >> I've noticed that Windows Server 2016 has a congestion control provider >> setting set to "default", while previous versions of Windows has this >> setting set to "none". >> >> I've created a topic on OpenVPN Support Forum and it was suggested to >> post >> my issue to you and reference the thread. >> >> You can reference to the >> https://forums.openvpn.net/viewtopic.php?f=6&t=27173 for config files and >> additional information. >> >> Have you faced a similar issue before? Can you provide any hint how can I >> resolve the issue? What did I missed? >> I would be very grateful for any help. Thank you in advance. >> >> >> >> >> _______________________________________________ >> Openvpn-devel mailing list >> Openvpn-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/openvpn-devel >> > > > _______________________________________________ > Openvpn-devel mailing list > Openvpn-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/openvpn-devel _______________________________________________ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
