Vyatta Network OS Documentation

Learn how to install, configure and operate the Vyatta NOS, which helps drive our virtual networking & physical platforms portfolio.

ECMP overview

ECMP is a technique that routes packets along multiple paths of equal cost. ECMP provides a load-balancing mechanism to ensure optimum usage of a routing path.

Vyatta NOS supports the following load-balancing mechanisms:

  • Modulo-n-hash
  • Hash-threshold
  • Highest Random Weight (HRW)

Vyatta NOS calculates the key of the packet flow for every ECMP selection algorithm. The next-hop selection algorithm calculates the key of the flow and chooses the next hop.

Vyatta NOS supports the HRW load-balancing mechanism by default. You can change the ECMP mode, if required.

ECMP is enabled on Border Gateway Protocol (BGP) by configuring the maximum number of ECMP routes for External BGP (eBGP) or Internal BGP (iBGP).