Q:

How do I check DHCP lease time in systemd-networkd? 

How do I find the DHCP lease time when I am using systemd-networkd? 
My network is defined in /etc/systemd/network/eth0.network:
[Match]
Name=eth0

[Network]
DHCP=yes

There are other question on this site asking for the same information but they weren't using systemd-networkd but dhclient or some other method. 
I've tried looking in journalctl to no avail.  I’m using ArchLinux.  

A:

Depending on the OS; Enabling debug isn't always necessary. 
systemd-networkd should store the lease info under /run/systemd/netif/leases/
i.e.
cat /run/systemd/netif/leases/2

A:

Per Lennart's post here, you have to change  systemd-networkd log level to debug. 
If you wanted to have it on all the time you could use a drop-in unit:
mkdir -p /etc/systemd/system/systemd-networkd.service.d
cat << IN > /etc/systemd/system/systemd-networkd.service.d/10-debug.conf
[Service]
Environment=SYSTEMD_LOG_LEVEL=debug
IN
systemctl daemon-reload
systemctl restart systemd-networkd

