dhcpcd-discuss

On 03/03/18 09:30, Roy Marples wrote:
> On 03/03/2018 02:26, jobhunts02@xxxxxxx wrote:
> > When I pull the cable to the interface on which I got an IPv4 address 
> > via DHCP, I would like the address to be deleted.  The reason it is 
> > not deleted is that state is NULL in ipv4ll_freedrop, which prevents 
> > ipv4_deladdr from being called.  If an interface has obtained an IPv4 
> > & IPv6 address via DHCP, neither address is deleted when the cable is 
> > pulled.  If the interface only has an IPv6 address via DHCP, the 
> > address does get deleted when the cable is pulled.
> >
> > Is there a way to ensure that addresses obtained via DHCP will be 
> > deleted when the cable is pulled?
>
> Which OS are you using (please specify kernel version)?
> Which dhcpcd version are you using?
>
> I ask, because on NetBSD-8 and newer, the behaviour is to keep the 
> addresses alive on carrier down as the kernel will deny their usage 
> until they are revalidated by the kernel DaD's mechanism.
>
> Now, this could also be a bug in dhcpcd where this is not respected for 
> other kernels and the behaviour should be as you describe - all 
> addresses dhcpcd is responsible for should be removed at carrier down.

$ uname -a
Linux uberpc.marples.name 4.14.0-3-amd64 #1 SMP Debian 4.14.17-1 
(2018-02-14) x86_64 GNU/Linux

Although it's reported as Debian, the OS is SparkyLinux

$ sudo ./dhcpcd -dB --nodhcp
dhcpcd-7.0.1 starting
eth0: executing `/libexec/dhcpcd-run-hooks' PREINIT
eth0: executing `/libexec/dhcpcd-run-hooks' NOCARRIER
wlan0: executing `/libexec/dhcpcd-run-hooks' PREINIT
wlan0: executing `/libexec/dhcpcd-run-hooks' CARRIER
DUID 00:01:00:01:21:66:22:a8:7c:5c:f8:59:7b:b2
wlan0: IAID f8:59:7b:b2
wlan0: adding address fe80::9497:7b15:fa4b:c108
wlan0: pltime infinity, vltime infinity
wlan0: delaying IPv6 router solicitation for 0.8 seconds
wlan0: delaying IPv4 for 0.5 seconds
eth0: waiting for carrier
wlan0: using IPv4LL address 169.254.189.240
wlan0: adding route to 169.254.0.0/16
wlan0: adding default route
wlan0: ARP announcing 169.254.189.240 (1 of 2), next in 2.0 seconds
wlan0: executing `/libexec/dhcpcd-run-hooks' IPV4LL
wlan0: soliciting an IPv6 router
wlan0: delaying Router Solicitation for LL address
wlan0: sending Router Solicitation
wlan0: Router Advertisement from fe80::1
wlan0: adding address fd73:7808:1015:0:a371:3c19:c535:9c8b/64
wlan0: pltime 120 seconds, vltime 180 seconds
wlan0: adding route to fd73:7808:1015::/64
wlan0: adding default route via fe80::1
wlan0: waiting for Router Advertisement DAD to complete
wlan0: reading lease `/var/db/dhcpcd/wlan0-UberNET.lease6'
wlan0: soliciting a DHCPv6 lease
wlan0: delaying SOLICIT6 (xid 0xce3e6f), next in 0.6 seconds
wlan0: ARP announcing 169.254.189.240 (2 of 2)
wlan0: broadcasting SOLICIT6 (xid 0xce3e6f), next in 0.9 seconds
wlan0: ADV fd73:7808:1015::1a3/128 from fe80::1
wlan0: broadcasting REQUEST6 (xid 0x4636d1), next in 1.1 seconds
wlan0: REPLY6 received from fe80::1
wlan0: adding address fd73:7808:1015::1a3/128
wlan0: pltime 75 seconds, vltime 120 seconds
wlan0: renew in 37, rebind in 60, expire in 120 seconds
wlan0: writing lease `/var/db/dhcpcd/wlan0-UberNET.lease6'
wlan0: waiting for DHCPv6 DAD to complete
wlan0: Router Advertisement DAD completed
wlan0: executing `/libexec/dhcpcd-run-hooks' ROUTERADVERT
wlan0: DHCPv6 DAD completed
wlan0: executing `/libexec/dhcpcd-run-hooks' BOUND6
wlan0: fe80::1 is unreachable, expiring it
wlan0: executing `/libexec/dhcpcd-run-hooks' ROUTERADVERT
wlan0: Router Advertisement from fe80::1
wlan0: adding address fd73:7808:1015:0:a371:3c19:c535:9c8b/64
wlan0: pltime 120 seconds, vltime 180 seconds
wlan0: executing `/libexec/dhcpcd-run-hooks' ROUTERADVERT
wlan0: carrier lost
wlan0: executing `/libexec/dhcpcd-run-hooks' NOCARRIER
wlan0: deleting address fd73:7808:1015::1a3/128
wlan0: executing `/libexec/dhcpcd-run-hooks' EXPIRE6
wlan0: deleting address fd73:7808:1015:0:a371:3c19:c535:9c8b/64
wlan0: deleting route to fd73:7808:1015::/64
wlan0: deleting default route via fe80::1
wlan0: executing `/libexec/dhcpcd-run-hooks' ROUTERADVERT
wlan0: deleting address fe80::9497:7b15:fa4b:c108
wlan0: deleting IP address 169.254.189.240/16
wlan0: deleting route to 169.254.0.0/16
wlan0: deleting default route
wlan0: executing `/libexec/dhcpcd-run-hooks' IPV4LL
wlan0: executing `/libexec/dhcpcd-run-hooks' EXPIRE

So I issued pkill wpa_supplicant to trigger the carrier down and as you 
can see, every address dhcpcd was responsible for has been removed at 
carrier down.

I need you to supply the same sort of log - add debug to dhcpcd.conf, to 
show that dhcpcd assigned an address but did not remove it at carrier down.

Thanks

Roy