root@SD6-Casa:~# grep -i dhcp /var/log/syslog
Apr 12 07:38:38 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 07:38:38 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 07:38:38 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 07:42:35 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 07:42:35 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 07:42:35 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 07:42:35 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 07:47:30 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 07:47:30 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 07:47:30 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 07:52:25 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 07:52:25 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 07:52:25 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 07:56:20 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 07:56:20 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 07:56:20 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
Apr 12 08:00:35 SD6-Casa dhclient: DHCPREQUEST on eth0 to 192.168.0.2 port 67
Apr 12 08:00:35 SD6-Casa dhclient: DHCPACK from 192.168.0.2
Apr 12 08:00:35 SD6-Casa dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied
[....]
I can confirm this bug, and it might be related with Bug #33968.