Admitting I know very little about apparmor, here is the profile that worked for me: # cat /etc/apparmor.d/usr.sbin.dhcpd
# vim:syntax=apparmor #include <tunables/global> /usr/sbin/dhcpd { #include <abstractions/base> #include <abstractions/nameservice> capability chown, capability dac_override, capability net_bind_service, capability net_raw, capability setgid, capability setuid, capability sys_chroot, network inet raw, network packet raw, /etc/dhcp/dhcpd.conf r, /etc/dhcp/dhcpd6.conf r, /etc/bind/* r, /etc/hosts.allow r, /etc/hosts.deny r, @{PROC}/net/dev r, /usr/sbin/dhcpd rmix, /var/lib/dhcp/dhcpd.leases* rwl, /var/lib/dhcp/dhcpd6.leases* rwl, /{,var/}run/dhcp-server/dhcpd.pid wl, } -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to isc-dhcp in Ubuntu. https://bugs.launchpad.net/bugs/1901373 Title: isc-dhcp-server AppArmor Denied on /proc/sys/net/ipv4/ip_local_port_range Status in isc-dhcp package in Ubuntu: Confirmed Bug description: The following AppArmor denial errors are shown on startup: Oct 25 00:52:00 xxx kernel: [ 556.231990] audit: type=1400 audit(1603601520.710:32): apparmor="DENIED" operation="open" profile="/usr/sbin/dhcpd" name="/proc/sys/net/ipv4/ip_local_port_range" pid=1982 comm="dhcpd" requested_mask="r" denied_mask="r" fsuid=0 ouid=0 Oct 25 00:52:00 xxx kernel: [ 556.232257] audit: type=1400 audit(1603601520.710:33): apparmor="DENIED" operation="open" profile="/usr/sbin/dhcpd" name="/proc/sys/net/ipv4/ip_local_port_range" pid=1982 comm="dhcpd" requested_mask="r" denied_mask="r" fsuid=0 ouid=0 Fix is to edit /etc/apparmor.d/local/usr.sbin.dhcpd to have: @{PROC}/sys/net/ipv4/ip_local_port_range r, 'lsb_release -rd': Description: Ubuntu 20.04.1 LTS Release: 20.04 isc-dhcp-server: Installed: 4.4.1-2.1ubuntu5 Candidate: 4.4.1-2.1ubuntu5 Version table: *** 4.4.1-2.1ubuntu5 500 500 http://us.archive.ubuntu.com/ubuntu focal/main amd64 Packages 100 /var/lib/dpkg/status apparmor: Installed: 2.13.3-7ubuntu5.1 Candidate: 2.13.3-7ubuntu5.1 Version table: *** 2.13.3-7ubuntu5.1 500 500 http://us.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages 100 /var/lib/dpkg/status 2.13.3-7ubuntu5 500 500 http://us.archive.ubuntu.com/ubuntu focal/main amd64 Packages To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/isc-dhcp/+bug/1901373/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp