I've been using the Mikrotik OS purely as an Ethernet Router for some years now. The router is based around a VIA motherboard and quad port Ethernet Card. My initial use was purely as a router that enabled various subnets to share a 1.5MBit ADSL Internet connection.

Recently I installed a couple of servers and this is when I first noticed that I had some throughput issues. Specifically I noticed that workstations that were attempting to access a server on a different subnet weren't getting particularly good performance.

When I did a bandwidth test from a workstation to the router using the Mikrotik btest software, I was typically getting a sustained bit rate in the order of 92MBit/sec. However, when I ran the Bandwidth test software in server mode on any server or workstation on the network, and attempted to run the test from a workstation on another subnet, therefore forcing the traffic to traverse the network through the Mikrotik router, I was getting quite poor performance, anything from 5MBit/sec to 15MBit/sec. Looking at things like the CPU load on the router, it was only sitting at around 30%.

The Ethernet card that I was running at the time was the DLINK DFE-580TX. Whilst I know that this card has known issues, I've never had any issues whatsoever with the system locking up. However, working IT myself I knew that everyone would simply blame the ethernet card. I have subsequently replaced the card with a DLINK DFE-570TX, and it has made no difference and I am seeing the exact same behaviour.

I've even tried reducing the configuration down to a very simplistic one where I am not doing any firewalling, mangling etc to ensure that these activities weren't a factor, but again it made no difference.

Has anyone else had this issue or have any insight into why I am seeing such poor throughput when traffic traverses from one ethernet port to another?

Richard

I was actually just coming here to post the same thing. Today, well doing some testing I noticed the same issues, not as drastic but about 100k loss for every mikrotik I added linked together. You are not the only one seeing these issues.

Setup is all routerboard 532's

-T3C

Hi T3C

All routers will introduce a small overhead as they strip the MAC addresses off the packet, examine the TCP/IP header to determine the route, and then re-encapsulate the packet with new MAC addresses for the destination subnet.

Having said this, and assuming you mean a performance degradation of 100kbit/sec per Mikrotik router, my experience with CISCO routers suggests that what you are experiencing is higher than it should be.

Hopefully one of the Mikrotik support people posts their thoughts on both of our problems...

Richard

You are very accurate in your description of how the packets travel accross their respective paths.

Using Mikrotik on the RouterBoard 532 you will experience a MAJOR latency increase if you are bridging any interfaces. If you are not using any sort of bridging, then the latency can only come from the overhead of the hardware that the RouterOS is installed on.

I have installed the Mikrotik RouterOS on a couple P4 3.0Ghz Machines and had very little problems with latency. I was using intel based network cards (Mikrotik seems to like Intel or Realtek based Network cards a lot more) and experienced very little, if any, latency issues.

You are very accurate in your description of how the packets travel accross their respective paths.

Using Mikrotik on the RouterBoard 532 you will experience a MAJOR latency increase if you are bridging any interfaces. If you are not using any sort of bridging, then the latency can only come from the overhead of the hardware that the RouterOS is installed on.

I have installed the Mikrotik RouterOS on a couple P4 3.0Ghz Machines and had very little problems with latency. I was using intel based network cards (Mikrotik seems to like Intel or Realtek based Network cards a lot more) and experienced very little, if any, latency issues.

I did have ether1 and ether2 bridged when running the tests. I will route and try it again.
Thanks for the reply.