Since upgrade to 3.27 (including bios to 2.20) on RB411 some clients have problem with the ethernet connection. I have to set Auto Negotiation disabled, otherwise there is sometimes no connection (R) between RB LAN interface and the ethernet card .

with what devices exactly you have such problems?

Hello,

We have a similar issue.
The Mikrotik RB1100 (4.1) is connected in bridge mode (port 11&12, bypass=0) to our cisco 3750 router.

In auto-neg mode, the traffic is interrupted during 3 seconds every X seconds (about 1 minute).

We tried to remove autoneg and force 1Gbps/fullduplex, but we lost connection with the mikrotik (it's surprising because we didn't change our management port (port 1)).

Is it a known problem?
Best Regards
Brice

We extended the tests.

In mikrosite website, we found that autoneg must be enabled with 1 gbps.

So we go to 100mbps speed.
We tested auto, half and full duplex. And auto was the more efficient.
The bridge worked without loosing packets until we activate the firewall mangles rules.
Then we lost packets and a lot of Tx/Rx errors appear. (we lost ping packets through the mikrotik)

Perfs :
CPU went from 10% to 16%, 480Mio free, and 2000 pps each way on each interface of the bridge.

Have you an idea/solution ?
can it be a performance issue ?

Best Regards
Brice

For information

I switched to a RB1000 with a 1,33Ghz proc (on 4.11 os)

It worked much better and I could see the processor reaching 100% load during long periods.

After a redesign of mangle rules (passthrough deactivation and most popular rules first), the mikrotik runs with about 30% load of CPU (much better).

We will proceed to a prod test soon.