dhcpcd-discuss

Hello guys, in first, thanks a lot for great linux component which met 
most RFC's :)

Im looking for solution where have "dhcpcd" which is started as systemd 
daemon, with "-p -q -b wlan0" args, client is always online and there is 
no event which may stop or restart dhcpcd. Also, client is mostly used 
for IPv4ll (IPv4 Link-local addressing, dhcpcd is optional but not 
mandatory, wlan0 wpa_supplicant is always online.

But im facing with little problem, im need to keep IPv4 address on 
interface(and on dhcpcd) when wlan0 link states are changes with "ip 
link set wlan0 down" -> -> "ip link set wlan0 up", but during this 
update, dhcpcd will lost IPv4LL address and dhcpcd will generate new one.

|e.g. stages: 1) boot process, dhcpcd will generate 169.254.8.37 as 
link-local ip address on wlan0 interface 2) $: ifconfig -> wlan0:addr 
169.254.8.37 3) $: ip link set wlan0 down 4) $: sleep 20 5) $: ip link 
set wlan0 up 6) $: ifconfig -> wlan0: 169.254.37.137 |

--persistent, --reconfigure does not help to solve situation. Any ideas 
how i can keep dhcpcd/wlan0 interface ipaddress when down&up?

System: Yocto (warrior), Linux 4.14.98

Thanks F.