A debian jessie device connection via ppp to the internet
We use systemd-networking and no /etc/network/interface at all.
systemd-resolved is used for DNS.
systemctl --version systemd 230 +PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ -LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD +IDN armv7l GNU/Linux kernel 4.4.14-v7+
(versions are the ones from jessie-backports)
This works fine for Ethernet + W-Lan, but fails for ppp.
Reason: the custom hook up scripts
are still writing to /etc/resolv.conf instead of connecting to the dbus server systemd-resolved provides.
so i am trying to get the PPP interface to have DNS resolution, which should be possible by calling SetLinkDNS via DBUS from what i did read (links at the end)
Get the interface ID (5 in our case)
ip l .. 5: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 700 qdisc pfifo_fast state UNKNOWN mode DEFAULT group default qlen 3 link/ppp ..
Read out current status of link interface 5
busctl introspect org.freedesktop.resolve1 /org/freedesktop/resolve1/link/_35 |grep DNS .DNS property a(iay) 0 -
set DNS on Interface 5 with 1 IPV4 Address (google DNS as example) (whats the explanation of the 3rd integer?)
busctl call org.freedesktop.resolve1 /org/freedesktop/resolve1 org.freedesktop.resolve1.Manager SetLinkDNS 'ia(iay)' 5 1 2 4 8 8 8 8 Link ppp0 is managed.
Read out values, still empty, so it failed to insert those value.
busctl introspect org.freedesktop.resolve1 /org/freedesktop/resolve1/link/_35 |grep DNS .DNS property a(iay) 0
So how do i debug this further to finally get it working?
falling back to /etc/network/interfaces or a "normal" /etc/resolv.conf is not an option.
Resources i used (plus a lot more but those are the relevant ones):