MikroTik

hallo,

I have a RB2011L an OS 6.4.

ETH1: Gigabit Uplink to Provider
ETH2: some other Network devices, also GBit
ETH3: small Server with public IP, Gigabit
MTUs are on 1500 on all interfaces

This is all direct IP configuration, public IPs & static routes, no PPPoE, no VLANs, etc.

The issue is that the server on ETH3 can
- upload as fast as possible with another servers on the Internet, eg. 100 MBit
- but downloads are much too slow, about 10-20 MBit

When setting the Interface-Rate of ETH3 Interface from GBit to 100 MBit full duplex, I am getting only 2 MBit with the download. The upload is still fine then.
When setting the Rate of ETH3 Interface to 100 MBit half duplex, I am getting 10-15 MBit.
Changing MTUs does not really make a difference.

Does this make any sense to anyone?

Did I forget to configure something about the Ethernet Interfaces? Is there something special about Gigabit-Links?

I need to add:

I doubt that the issue is related to a "weakness" on my internet-uplink, because this could not really explain the behaviour when changing Ethernet-Interface-Datarates. Also in a different setup I observed the same issue when transfering between two local servers here.

It does not matter if the transfer is from/to the internet or between local devices. There is always one direction that is crippled.

Problem solved:
My setup was completely fine,
but there was something wrong with the fiber connetion to my provider.
This was causing massive frame loss if speeds going above 100 MBit.

Problem solved:
My setup was completely fine,
but there was something wrong with the fiber connetion to my provider.
This was causing massive frame loss if speeds going above 100 MBit.

What was the problem with the provider? how did you diagnose it?

we have a virgin connection here in the UK and are noticing something similar.

Thanks.

Problem solved:
My setup was completely fine,
but there was something wrong with the fiber connetion to my provider.
This was causing massive frame loss if speeds going above 100 MBit.

Hi captainproton

We're seeing very similar symptoms.
Upload fast. Download slow
What was the problem with you fiber provider?

Clients on PPPoE with static IP assigned on CCR using src-nat
Speed throttling seems to go up and down, so we're struggling to work out of there's a problem with the CCR or externally.

Sometimes the whole CCR seems to be in "go-slow" - so when logged in via Winbox it takes a while for windows to populate or refresh.

Any ideas!??