XLB - XDP Load Balancer

A Linux XDP based load balancer, which currently supports only IPv4 traffic.

Prerequisite

• Add VIP to the loopback device E.g.:

  $ ip addr add 10.10.0.5/8 dev lo
  

  where 10.10.0.5 is the VIP.
• Configure ARP settings Possible configuration would be:

  $ sysctl net.ipv4.conf.all.arp_ignore=1
  $ sysctl net.ipv4.conf.eth0.arp_ignore=1
  $ sysctl net.ipv4.conf.all.arp_announce=2
  $ sysctl net.ipv4.conf.eth0.arp_announce=2
  

With these adjustments, the LB can do DSR (Direct Server Return) properly with VIP as source address of the response.

Build

Since we use libbpf as our eBPF library, we need pull it first:

$ git submodule update --init

Then simply run make to build both control plane and data plane sources.

TODOs

• LRU for faster routing decision
• IPv6 support
• Better routing decision algorithm (we're using modulo devision currently)