answer at bottom
I have a dell xps 9360 13" connected to a dell d6000. Connecting to the display port results in a blank monitor, when I connect via hdmi it displays, as on the d6000 there is only one hdmi and 2 display ports this isn't ideal.
When I connect and disconnect a monitor from the display port, both the hdmi connect monitor and the laptop screen turn on and off, so something is being registered.
Any ideas on how I remedy this?
UPDATE
Re justin's response
I believe I had already installed the latest display link drivers. When I decided to retry this process as per the answer, i get this response which I don't beleieve I got before.
Verifying archive integrity... 100% All good.
Uncompressing DisplayLink Linux Driver 4.4.24 100%
DisplayLink Linux Software 4.4.24 install script called: install
Distribution discovered: elementary OS 5.0 Juno
Installing
Configuring EVDI DKMS module
Registering EVDI kernel module with DKMS
Building EVDI kernel module with DKMS
Installing EVDI kernel module to kernel tree
EVDI kernel module built successfully
Installing x64-ubuntu-1604/DisplayLinkManager
Installing libraries
Installing firmware packages
Installing licence file
Adding udev rule for DisplayLink DL-3xxx/5xxx devices
Warning: The unit file, source configuration file or drop-ins of dlm.service changed on disk. Run 'systemctl daemon-reload' to reload units. Job for dlm.service failed because the control process exited with error code.
systemctl status dlm.service Warning: The unit file, source configuration file or drop-ins of dlm.service changed on disk. Run 'systemctl daemon-reload' to reload units. ● dlm.service - DisplayLink Manager Service Loaded: loaded (/lib/systemd/system/dlm.service; static; vendor preset: enabled) Active: activating (auto-restart) (Result: exit-code) since Wed 2019-01-30 10:12:11 CET; 564ms ago Process: 16175 ExecStartPre=/bin/sh -c modprobe evdi || (dkms install evdi/4.4.24 && modprobe evdi) (code=exited, status=1/FAILURE)
second update
I tried uninstalling and reinstalling,
but the dlm.service is still struggling.
-- Unit dlm.service has begun starting up. Jan 30 20:46:26 sico-XPS-13-9360 sh[17515]: modprobe: ERROR: could not insert 'evdi': Required key not available
Jan 30 20:46:26 sico-XPS-13-9360 kernel: PKCS#7 signature not signed with a trusted key
Jan 30 20:46:26 sico-XPS-13-9360 sh[17515]: Module evdi/4.4.24 already installed on kernel 4.15.0-44-generic/x86_64
Jan 30 20:46:26 sico-XPS-13-9360 sh[17515]: modprobe: ERROR: could not insert 'evdi': Required key not available
Jan 30 20:46:26 sico-XPS-13-9360 systemd[1]: dlm.service: Control process exited, code=exited status=1
Jan 30 20:46:26 sico-XPS-13-9360 systemd[1]: dlm.service: Failed with result 'exit-code'.
Jan 30 20:46:26 sico-XPS-13-9360 systemd[1]: Failed to start DisplayLink Manager Service.
I'm reading that this error Jan 30 20:46:26 sico-XPS-13-9360 kernel: PKCS#7 signature not signed with a trusted key
might be related to secure boot being on (i dual boot with elementary and windows 10) or an nvidia driver issue.
Answer
Install driver as indicated in Justin's answer and disable secure boot to make sure dlm.service can function as expected