Compatibility issue with Open VPN

[hiroko45]

Hello :-)

First of all THANK YOU for your great work !!

Description of the problem

The drivers work like a charm in normal operation , but when initiating a connexion with Open VPN the following occur :

The Synology built in Open VPN connexion client connect properly to its server ( in my case Express VPN ) The number of received bytes ( from the VPN connexion ) is increasing The number of sent bytes stay at zero ( or increase very slowly )

The consequence is that the NAS is unable to download packet from the synology store or access the internet.

The issue does not affect the LAN traffic, but only the open VPN connexion

When switching back to the Synology internal network card , the Open VPN connexion works fine. If both device are connected ( internal card and the usb adapter ) at the same time the same problem occur.

Description of your products

Model(platform): DS918+ (apollolake) DSM version: e.g. 7.1.1-42692 Update 5 Driver version: 2.15.0-3 Ethernet device: e.g. XRR brand ( from Amazon) based on RTL8156B Working status: e.g. Stable Maximum Throughput: e.g. 2.18 Gbps @ MTU 9000 in iperf3 (very stable I have transfered 50TB of data without any issue ) USB port: Front one

Kind regards :-)

Rémy

[mdstoll]

I had the same issue running both port 1 and an external adapter for 5GbE. When I set the MTU of the latter to 9000 the network had to restart. This also resulted in the VPN being accessible again.

Maybe coincidence? But it works for me.

[bb-qq]

@hiroko45 If you till have problem, could you try mssfix 1300 for OpenVPN configuration?