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+---
+layout: post
+title: "Linux on Dell Precision 7520"
+date: 2017-11-29 12:00:00 +0100
+comments: true
+categories: 
+---
+
+Three years after the [M4800]({% post_url 2014-11-22-debian-jessie-on-dell-precision-m4800 %}),
+it's time to upgrade again. Let's start with `debian-9.2.1-amd64-netinst.iso`.
+
+Booting it up
+-------------
+
+My new laptop came with an OEM Windows 10 preinstalled. I wanted to keep it just
+in case, but it turns out that:
+
+  * since I want BitLocker, SecureBoot needs to be enabled
+  * Ubuntu supports SecureBoot, but Debian does not
+  * since I want LVM+encryption, I need to use Debian
+
+So I'm ditching the pre-installed Windows (I'll make a VirtualBox VM
+later on if I really need it).
+
+Installation
+------------
+
+System install is pretty uneventful, except for the fact that the trackpad
+is apparently not working within the installer. I was able to install
+on LVM with encryption as desired. I was happy to find MATE as one of the
+desktop options.
+
+Post-install customization
+--------------------------
+
+X11
+===
+
+Keyboard and trackpad setup appear to work just fine out of the
+box (including for GDM).
+
+The default driver appears to work just fine with the embedded LCD
+display, but is unable to handle my two external DP monitors
+(see below).
+
+Nvidia driver
+=============
+
+I am using this laptop on a docking station with two DisplayPort
+monitors. This works only if the builtin Intel GPU is disabled,
+and the add-on Nvidia GPU only is enabled.
+
+Using the nvidia (non-free) driver
+----------------------------------
+
+To install the nVidia driver:
+
+* make sure installed kernel headers (linux-headers) match kernel (linux-image),
+  otherwise DKMS won't build.
+* install nvidia-driver (note: this will build a kernel module, so requires
+  a working compiler)
+* install nvidia-xconfig
+* run `nvidia-xconfig --query-gpu-info` by hand and make note of PCI BusID
+* run `nvidia-xconfig --busid=PCI:x:x:x` to generate xorg.conf
+
+BIOS setup
+----------
+
+To disable the built-in Intel GPU:
+
+* Video -> Switchable graphics -> uncheck Enable Switchable Graphics
+
+(I have also checked Graphics Special Mode, not sure whether this is
+needed).
+
+Desktop environment
+===================
+
+* Set focus-follows-mouse
+* Set keyboard shortcut for lock screen to Win+L
+* Set MATE terminal to white-on-black
+
+[Disable GNOME Keyring SSH agent](http://william.shallum.net/random-notes/disabling-gnome-keyring-daemon-ssh-agent-on-mate-desktop):
+
+```
+$ gsettings get org.mate.session gnome-compat-startup
+['smproxy', 'keyring']
+$ gsettings set org.mate.session gnome-compat-startup "['smproxy']"
+$ gsettings get org.mate.session gnome-compat-startup
+['smproxy']
+
+$ mate-session-properties
+# uncheck SSH Key Agent and maybe others.
+# This will create a copy of /etc/xdg/autostart/gnome-keyring-ssh.desktop
+# in ~/.config/autostart, with appropriate settings to turn it off.
+```
+
+Sudo configuration
+==================
+
+Add myself to group `sudo`.
+
+APT sources
+===========
+
+In `/etc/apt/sources.list`: add contrib and non-free.
+
+Wifi drivers
+============
+
+The Intel wireless drivers require non-free binary components,
+see https://wiki.debian.org/fr/iwlwifi
+
+Packages
+========
+
+firmware-iwlwifo
+vim
+rsync
+net-tools
+pcscd
+apt-transport-https
+openvpn
+binutils
+ltrace
+strace
+scdaemon
+
+Hipchat
+=======
+
+Hipchat is linked against Qt libraries that assume OpenSSL 1.0,
+but Debian provides 1.1.
+
+Work around:
+
+```
+# apt-get install libssl1.0.2
+# ln -s /usr/lib/x86_64-linux-gnu/libssl.so.1.0.2 /opt/HipChat4/lib/libssl.so
+# ln -s /usr/lib/x86_64-linux-gnu/libcrypto.so.1.0.2 /opt/HipChat4/lib/libcrypto.so
+```
+
+(Note: the Atlassian web site gives
+[incomplete instructions](https://confluence.atlassian.com/hipchatkb/hipchat4-debian-client-doesn-t-connect-859526103.html)
+-- they do not mention libcrypto).
+