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Applies to RouterOS: v6.29 +


IPv4 FastTrack handler is automatically used for marked connections. Use firewall action "fasttrack-connection" to mark connections for fasttrack. Currently only TCP and UDP connections can be actually fasttracked (even though any connection can be marked for fasttrack). IPv4 FastTrack handler supports NAT (SNAT, DNAT or both).

Note that not all packets in a connection can be fasttracked, so it is likely to see some packets going through slow path even though connection is marked for fasttrack. Fasttracked packets bypass firewall, connection tracking, simple queues, queue tree with parent=global, ip traffic-flow(restriction removed in 6.33), ip accounting, ipsec, hotspot universal client, vrf assignment, so it is up to administrator to make sure fasttrack does not interfere with other configuration;


IPv4 FastTrack is active if following conditions are met:

  • no mesh, metarouter interface configuration;
  • sniffer, torch and traffic generator is not running;
  • no active mac-ping, mac-telnet or mac-winbox sessions restriction removed in 6.33;
  • /tool mac-scan is not actively used;
  • /tool ip-scan is not actively used;

Supported hardware

Fasttrack is supported on the listed devices.

RouterBoard Interfaces
RB6xx series ether1,2
RB7xx series all ethernets
RB800 ether1,2
RB9xx series all ethernets
RB1000 all ethernets
RB1100 series ether1-10,11
RB2011 series all ethernets and sfp
CCR series routers all ethernets and sfps
All devices wireless interfaces, if wireless-fp or wireless-cm2 package used


Initial configuration

For example, in home routers with factory default configuration, you could Fasttrack all LAN traffic with this one rule placed at the top of the Firewall Filter. The same configuration accept rule is required:

/ip firewall filter add chain=forward action=fasttrack-connection connection-state=established,related
/ip firewall filter add chain=forward action=accept connection-state=established,related

Simple FastTrack rule in the firewall, you will need other filter or mangle rules to get the advantage of the FastTrack:

  • /ip firewall filter
Fasttrack1 example.png
  • /ip firewall mangle

Warning: Queues, firewall filter and mangle rules will not be applied for FastTracked traffic.

  • Connection is FastTracked until connection is closed, timed-out or router is rebooted.
  • Dummy rules will dissapear only after FastTrack firewall rules will be deleted/disabled and router rebooted.

FastTrack on RB2011

FastTrack is enabled on RB2011 at chain=forward with the rule from previous exampke. Bandwidth test with single TCP stream is sent, Fasttrackon2011.png