Include this example file in the tarball on how to do load balancing with nftables, inspired from https://wiki.nftables.org Signed-off-by: Arturo Borrero Gonzalez <arturo@xxxxxxxxxxxxx> --- files/examples/load_balancing.nft | 54 +++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100755 files/examples/load_balancing.nft diff --git a/files/examples/load_balancing.nft b/files/examples/load_balancing.nft new file mode 100755 index 0000000..128a443 --- /dev/null +++ b/files/examples/load_balancing.nft @@ -0,0 +1,54 @@ +#!/usr/sbin/nft -f + +# This example file shows how to implement load balancing using the nftables +# framework. +# This script is mean to be loaded with `nft -f <file>` +# You require linux kernel >= 4.12 and nft >= 0.7 +# For up-to-date information please visit https://wiki.nftables.org + +flush ruleset + +table ip nat { + chain prerouting { + type nat hook prerouting priority -300; + # round-robing load balancing between the 2 IPv4 addresses: + dnat to numgen inc mod 2 map { + 0 : 192.168.10.100, \ + 1 : 192.168.20.200 } + # emulate flow distribution with different backend weights using intervals: + dnat to numgen inc mod 10 map { + 0-5 : 192.168.10.100, \ + 6-9 : 192.168.20.200 } + # tcp port based distribution is also possible: + ip protocol tcp dnat to 192.168.1.100 : numgen inc mod 2 map { + 0 : 4040 ,\ + 1 : 4050 } + # consistent hash-based distribution: + dnat to jhash ip saddr . tcp dport mod 2 map { + 0 : 192.168.20.100, \ + 1 : 192.168.30.100 } + } +} + +table ip raw { + chain prerouting { + type filter hook prerouting priority -300; + # using stateless NAT, round-robing distribution (you could use hashing too): + tcp dport 80 notrack ip daddr set numgen inc mod 2 map { 0 : 192.168.1.100, 1 : 192.168.1.101 } + } +} + +table netdev mytable { + chain ingress { + # mind the NIC devices, they should exist + type filter hook ingress device eth0 priority 0; + # using Direct Server Return (DSR), connectionless approach: + udp dport 53 ether saddr set aa:bb:cc:dd:ff:ee ether daddr set numgen inc mod 2 map { + 0 : aa:aa:aa:aa:aa:aa, + 1 : bb:bb:bb:bb:bb:bb } fwd to eth1 + # using Direct Server Return (DSR), connection-oriented flows: + tcp dport 80 ether saddr set aa:bb:cc:dd:ff:ee ether daddr set jhash ip saddr . tcp sport mod 2 map { + 0 : aa:aa:aa:aa:aa:aa, + 1 : bb:bb:bb:bb:bb:bb } fwd to eth1 + } +} -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
