Hello,
I’m currently trying to migrate away from using FreeBSD as my MLPPP client for the internet connection. The problem I’m finding is that not all the websites are available with MikroTik in place. This is not an MTU problem. MTU, MRU and MRRU values have all been adjusted according to various available tunnels. FreeBSD can do this with MTU 1492 for all three values with no loss of packets. All websites work. I’ve tested on various 6.x versions of RouterOS. I’ve also tested on 5.x versions with the same effect. The problem has been noted at more then one location. The LNS at the provider is a cisco device, and a cisco router as the client does not experience this problem either.
Each DSL modem is about 3 mbit/s rate. If anyone has a setting I’ve missed I’ll try it and report back. However at this point I’m thinking its something about how RouterOS reassembles the packets in multilink mode.
Tried the following:
-
used various cat 5 / 5e / 6 cables from DSL modems to RB750
-
Changed DSL modems to different vendor, using latest firmware each time
-
Ensured each modem / DSL line was fully functional as an individual PPPoE connection during testing from laptop.
-
increased ICMP allowed rate from 10 to 64 to help PMTU
-
Changed Ethernet MTU rates from various sizes 1384 to 1492
-
set default PPP profile for MLPPP settings from ISP
-
disabled all firewall rules / enabled disabled fasttrack
-
Ensured device didn’t use more resources then given for CPU and Memory
*replaced the MikroTik with another MikroTik
- simplified the configuration as much as possible.
Typical RB750 config - also tested same effect as RB 2011
# jun/29/2016 13:20:33 by RouterOS 6.34.6
# software id =
/interface ethernet
set [ find default-name=ether1 ] name=ether1-lan
set [ find default-name=ether2 ] name=ether2-wan
set [ find default-name=ether3 ] name=ether3-wan
set [ find default-name=ether4 ] name=ether4-wan
set [ find default-name=ether5 ] name=ether5-wan
/interface pppoe-client
add add-default-route=yes allow=pap default-route-distance=1 disabled=no interface=\
ether2-wan,ether3-wan,ether4-wan,ether5-wan max-mru=1454 max-mtu=1454 mrru=1454 name=ISP \
password=passw0rd use-peer-dns=yes user=mppp%username@network
/ip ipsec proposal
set [ find default=yes ] enc-algorithms=3des
/ip pool
add name=default-dhcp ranges=192.168.88.10-192.168.88.254
/ip dhcp-server
add address-pool=default-dhcp disabled=no interface=ether1-lan lease-time=3d name=default
/system logging action
set 0 memory-lines=100
set 1 disk-lines-per-file=100
/ip address
add address=192.168.88.1/24 comment="default configuration" interface=ether1-lan network=\
192.168.88.0
/ip dhcp-client
add comment="default configuration" dhcp-options=hostname,clientid interface=ether1-lan
/ip dhcp-server network
add address=192.168.88.0/24 comment="default configuration" dns-server=8.8.4.4,8.8.8.8 \
gateway=192.168.88.1
/ip dns
set max-udp-packet-size=512
/ip dns static
add address=192.168.88.1 name=router
/ip firewall filter
add chain=input comment="default configuration" protocol=icmp
add chain=input comment="default configuration" connection-state=established
add chain=input comment="default configuration" connection-state=related
add chain=input dst-port=8291 protocol=tcp
add action=drop chain=input comment="default configuration" in-interface=mnsi
/ip firewall nat
add action=masquerade chain=srcnat comment="default configuration" out-interface=mnsi to-addresses=
0.0.0.0
/ip service
set api disabled=yes
/system clock
set time-zone-name=America/Toronto
/system identity
set name=RoubinTik
/system package update
set channel=bugfix
/tool mac-server
add interface=ether2-wan
add interface=ether3-wan
add interface=ether4-wan
add interface=ether5-wan
/tool mac-server mac-winbox
set [ find default=yes ] disabled=yes
add interface=ether2-wan
add interface=ether3-wan
add interface=ether4-wan
add interface=ether5-wan
Example of the dropped packets only when two or more links are active:
- with no other equipment but the two DSL modems and the the MikroTik with a laptop connected to it the problem can be experienced. Further to that, it can be proven that the MikroTik itself cannot use the internet link to even check for updates with the device.:
- simply disabling one of the links and the device can check for updates, and websites that didn’t work before now work.