To reproduce set address by dhcp , use load-balancing configuration:
```
set interfaces ethernet eth1 address 'dhcp'
set interfaces ethernet eth2 address 'dhcp'
set load-balancing wan interface-health eth1 failure-count '1'
set load-balancing wan interface-health eth1 nexthop 'dhcp'
set load-balancing wan interface-health eth1 success-count '1'
set load-balancing wan interface-health eth2 failure-count '1'
set load-balancing wan interface-health eth2 nexthop 'dhcp'
set load-balancing wan interface-health eth2 success-count '1'
set load-balancing wan rule 10 inbound-interface 'eth3'
set load-balancing wan rule 10 interface eth1
set load-balancing wan rule 10 interface eth2
set load-balancing wan rule 10 source address '198.51.100.0/24'
```
Force renew the DHCP address:
```
vyos@r14:~$ renew dhcp interface eth1
```
Logs hook [[ https://github.com/vyos/vyatta-wanloadbalance/blob/current/scripts/dhcp/04-dhcp-wanlb | 04-dhcp-wanlb ]] returned non-zero exit status:
```
May 08 12:40:37 r14 root[4623]: /etc/dhcp/dhclient-exit-hooks.d/04-dhcp-wanlb returned non-zero exit status 1
May 08 12:40:37 r14 systemd[1]:
[email protected]: Deactivated successfully.
May 08 12:40:37 r14 systemd[1]: Stopped
[email protected] - DHCP client on eth1.
May 08 12:40:37 r14 systemd[1]: Starting
[email protected] - DHCP client on eth1...
May 08 12:40:37 r14 systemd[1]: Started
[email protected] - DHCP client on eth1.
May 08 12:40:37 r14 sudo[4551]: pam_unix(sudo:session): session closed for user root
May 08 12:40:37 r14 dhclient-script-vyos[4628]: Current dhclient PID: 4627, Parent PID: 4626, IP version: 4, All dhclients for interface eth1: 4626 4627
May 08 12:40:37 r14 dhclient-script-vyos[4628]: Passing command to /usr/sbin/ip: "link set dev eth1 up"
May 08 12:40:37 r14 dhclient-script-vyos[4628]: No changes to apply via vyos-hostsd-client
May 08 12:40:37 r14 root[4656]: /etc/dhcp/dhclient-exit-hooks.d/04-dhcp-wanlb returned non-zero exit status 1
May 08 12:40:37 r14 dhclient[4627]: DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 5
May 08 12:40:40 r14 dhclient[4627]: DHCPOFFER of 192.168.100.254 from 192.168.100.1
May 08 12:40:40 r14 dhclient[4627]: DHCPREQUEST for 192.168.100.254 on eth1 to 255.255.255.255 port 67
May 08 12:40:40 r14 dhclient[4627]: DHCPACK of 192.168.100.254 from 192.168.100.1
```
Use `sudo kill -s SIGUSR2 $( cat $pid ) 2>/dev/null` seems fixes the bug