Device is CCR
ether2 10.9.8.254/24 and 10.9.9.254/24
Fileserver 10.9.8.100
Client1 10.9.8.2
Client2 10.9.9.2

Client 1 R/W speed to Fileserver is ~700-900Mbps
Client 2 R/W speed to Fileserver is ~100-300Mbps

No queue limits or smth.
When we set up DC and let the server do routing then Client1 and Client2 R/W speeds are ~same.

Why CCR routing hangs?
I googeled and found this http://stackoverflow.com/questions/2866 ... -interface BUT this is not normal. Also it didnt work.

Hi Ucom,
it looks like a 100% cpu utilization issue, you need to setup master port to enable the switch chip to do wire speed switching. To do that just select ether2 port as the master which will act as Layer 3 and set all the others (client 1, client2, fileserver) as slave then test the stuff again and throughput of both clients will be only dependent on fileserver performances.
Look here for examples http://wiki.mikrotik.com/wiki/Manual:Sw ... p_Features

Hi Ucom,
it looks like a 100% cpu utilization issue, you need to setup master port to enable the switch chip to do wire speed switching. To do that just select ether2 port as the master which will act as Layer 3 and set all the others (client 1, client2, fileserver) as slave then test the stuff again and throughput of both clients will be only dependent on fileserver performances.
Look here for examples http://wiki.mikrotik.com/wiki/Manual:Sw ... p_Features

Setting a master port won't help, as he is doing layer 3 routing and not layer 2 switching. Also, only the CCR1009 has a switch chip. (the OP didn't specify the model)

Ucom - I've seen this same issue with my CCR1016, It ended up being my Mangle rules. Also make sure you aren't NAT'ing between the two subnets, that will slow it down too. Unfortunately, RouterOS 6 doesn't fully support the multi-core processors. Routing, NAT and Mangle are all single thread processes, so once you max out that core, it's done.

Hi IntrusDave,

Device is CCR
ether2 10.9.8.254/24 and 10.9.9.254/24
Fileserver 10.9.8.100
Client1 10.9.8.2
Client2 10.9.9.2

Client 1 R/W speed to Fileserver is ~700-900Mbps
Client 2 R/W speed to Fileserver is ~100-300Mbps

Setting a master port won't help, as he is doing layer 3 routing and not layer 2 switching. Also, only the CCR1009 has a switch chip. (the OP didn't specify the model)

The OP is doing a mix of switching and routing, he has 2 networks running on the same L2 broadcast domain (eth2 has ip addresses from 2 different networks) plus client 1 to fileserver connection is around wirespeed, this is why I assumed he uses CCR1009 and I told him to use the switch chip also for client 2.

@Ucom: Can you please post the output of /export hide-sensitive so we can check where is your bottleneck?

Hi,

I've attached the configuration of another Mikrotik we have, but we're facing the same issue there.