# config system settingsset v4-ecmp-modesource-ip-based <----- Select next hop based on source IP.weight-based <----- Select next hop based on weight.usage-based <----- Select next hop based on usage.source-dest-ip-based <----- Select next hop based on both source and destination IPs.
This can be verified using the following command:
# diagnose sys vd listsystem fib version=37list virtual firewall info:------Truncated output ------name=root/root index=0 enabled use=112 rt_num=31 asym_rt=0 sip_helper=1, sip_nat_trace=1, mc_fwd=1, mc_ttl_nc=0, tpmc_sk_pl=0ecmp=source-ip-based, ecpm6=source-ip-based asym_rt6=0 rt6_num=32 strict_src_check=0 dns_log=1 ses_num=5 ses6_num=1 pkt_num=1158894tree_flag=1 tree6_flag=1 nataf=0 traffic_log=1 extended_traffic_log=0 svc_depth=2log_neigh=0, deny_tcp_with_icmp=0 ses_denied_traffic=no tcp_no_syn_check=0 central_nat=0 policy_mode_ngfw=0 block_land_attack=0 link_check_local_in=1fw_session_hairpin=no keep-PRP-trailer=0ipv4_rate=0, ipv6_rate=0, mcast6-PMTU=0, allow_linkdown_path=0mode=standalone ha_state=work prio=0 vid=0vf_count=5 vfe_count=17
To change the algorithm for IPv6, use the config system virtual-wan-link/config system sdwan on as per VDOM basis. The option selected here will apply to both IPv4 and IPv6.
# config system virtual-wan-link OR config system sdwanset status enable(virtual-wan-link) set load-balance-modesource-ip-based <----- Source IP load balancing. All traffic from a source IP is sent to the same interface.weight-based <----- Weight-based load balancing. Interfaces with higher weights have higher priority and get more traffic.usage-based <----- Usage-based load balancing. All traffic is sent to the first interface on the list. When the bandwidth on that interface exceeds the spill-over limit new traffic is sent to the next interface.source-dest-ip-based <----- Source and destination IP load balancing. All traffic from a source IP to a destination IP is sent to the same interface.measured-volume-based <----- Volume-based load balancing. Traffic is load balanced based on traffic volume (in bytes). More traffic is sent to interfaces with higher volume ratios.(virtual-wan-link) set load-balance-mode source-dest-ip-based(virtual-wan-link) end
Verify using following command:
(global) # diagnose sys vd listsystem fib version=37list virtual firewall info:------Truncated output ------name=root/root index=0 enabled use=112 rt_num=31 asym_rt=0 sip_helper=1, sip_nat_trace=1, mc_fwd=1, mc_ttl_nc=0, tpmc_sk_pl=0ecmp=source-dest-ip-based, ecpm6=source-dest-ip-based asym_rt6=0 rt6_num=32 strict_src_check=0 dns_log=1 ses_num=7 ses6_num=1 pkt_num=1161223tree_flag=1 tree6_flag=1 nataf=0 traffic_log=1 extended_traffic_log=0 svc_depth=2log_neigh=0, deny_tcp_with_icmp=0 ses_denied_traffic=no tcp_no_syn_check=0 central_nat=0 policy_mode_ngfw=0 block_land_attack=0 link_check_local_in=0fw_session_hairpin=no keep-PRP-trailer=0ipv4_rate=1, ipv6_rate=0, mcast6-PMTU=0, allow_linkdown_path=0mode=standalone ha_state=work prio=0 vid=0Related document.vf_count=5 vfe_count=17
https://docs.fortinet.com/document/fortigate/7.0.1/administration-guide/25967/equal-cost-multi-pathRelated Articles
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