Different Speeds from opposite ends of a VPN [Diagram]?

Notice: Page may contain affiliate links for which we may earn a small commission through services like Amazon Affiliates or Skimlinks.

IamSpartacus

Well-Known Member
Mar 14, 2016
2,515
650
113
If it only affects 10Gbe NICs it sounds like something can't handle receiving at that data rate and drops packets. This would trigger a backoff in transmission rates. This should converge at something near the available bandwidth, but it sounds like your congestion control is screwed up. You might also check your ethernet flow control settings and make sure they're consistent. If they're all currently on turn them off, and vice versa. (Flow control is often a bad idea, but sometimes helps.)
When you talk about my congestion and flow control settings, you mean in pfSense? I've never configured any of these on in pfSense of my core switch so whatever the defaults are is what they are currently set to.
 

mstone

Active Member
Mar 11, 2015
505
118
43
46
When you talk about my congestion and flow control settings, you mean in pfSense? I've never configured any of these on in pfSense of my core switch so whatever the defaults are is what they are currently set to.
congestion control is a tcp function. some firewall configs can screw it up. flow control is a function of the NICs and switches, with various devices having different defaults. before randomly trying to apply a bandwidth cap you should investigate those. :)