Tips & tricks

I wasn't able to set together a virtual mac address and a static IP using netplan: either the mac address didn't change, or IP was not set. I finally got the trick using a fake nic definition that matches the new virtual mac address I've set.    network:   renderer: networkd   ethernets:     ens160:       match:         macaddress: 00:0c:29:5a:69:00       macaddress: 00:50:56:0c:de:a6     ens160_2:       match:         macaddress: 00:50:56:0c:de:a6        addresses: [ 139.99.5.72/32 ]       nameservers:         addresses: [ 8.8.8.8 ]       routes:       - to: 0.0.0.0/0         via: 139.99.5.254      ...

apt install bluez hciattach /dev/ttyAMA0 bcm43xx 921600 systemctl restart bluetooth #1

As Ubuntu does officially support Raspberry PI 3 (arm64 and armhf) starting with 18.04.2 , I gave a try to the 64 bit version to be able using dotnet core with MongoDB as the later is discontinued in 32 bits architecture. I've downloaded and extracted the 32bits version of  aspnet core as the arm64 is not yet supported. But I've quickly found myself ending with an issue when trying to run the armhf dotnet app: -bash: /opt/dotnet/dotnet: No such file or directory Even if all the dotnet prerequisites were met. A few Googling hours later, I've figured out that, by default, no 32 bits (armhf) libraries are installed. Thought that can be done simply. First allow the armhf repository to be used in addition of arm64: dpkg --add-architecture armhf apt update Then add the armhf flavor of the dotnet prerequisites: apt install libunwind8:armhf gettext:armhf libc6:armhf libssl1.0-dev:armhf You can now enjoy running aspnet core 2.2 apps on a arm64 ubuntu 18.04 :-)...

If you got the error message "Cannot download packages whilst offline" but your internet connection is active, this is probably because you've managed the network configuration yourself and the network manager is reporting an offline status even if it's not correct. To fix this issue, simply edit the file /etc/NetworkManager/NetworkManager.conf and change the following configuration to be inline with: [ifupdown] managed=true Then restart the Network Manager : sudo service NetworkManager restart #1

In order to get TeamViewer running smoothly (without lag, or simply cannot install) when no monitors are connected, you need to emulate one. This is done by creating (or editing) this file : /usr/share/X11/xorg.conf.d/xorg.conf And add the following content : Section "Device" Identifier "Configured Video Device" Driver "dummy" EndSection Section "Monitor" Identifier "Configured Monitor" HorizSync 31.5-48.5 VertRefresh 50-70 EndSection Section "Screen" Identifier "Default Screen" Monitor "Configured Monitor" Device "Configured Video Device" DefaultDepth 24 SubSection "Display" Depth 24 Modes "1024x800" EndSubSection EndSection Reboot the computer #1

Edit the file /etc/hostname Load the name set in this file hostname -F /etc/hostname Edit the file /etc/hosts #1

If you wish to change the dns nameserver information in ubuntu 12.04, you have to use the file /etc/network/interfaces instead of /etc/resolv.conf . Edit /etc/network/interfaces and append or replace the following line to set your dns server : dns-nameservers 1.2.3.4 5.6.7.8 And optionally this one to specify the domain to be append when you request a non fully qualify name : dns-search foo.org bar.com #1

It could happen that your were connected to a Windows Domain and that you've decided to leave this domain. What about if all local users are disabled? You cannot join anew a Windows Domain as you don't own any local user able to connect in order to join the domain. You can still start your computer and see the login screen but you will definitely stay a click away from your desktop... Hopefully, there is a bunch of tools allowing you to enable anew the Administrator account and even reset the password : link1 link2 link3 ... (Simply search "offline windows password change" on Google) But in my case, editing the SAM file on another computer simply didn't work and I didn't want to burn a CD or corrupt my multiboot usbkey. So I've booted on Lubuntu already installed on my usbkey and decided to hex edit the file. Later on, I've found a linux tool called chntpw that could be installed on my live lubuntu distro and could do the trick, but I...

Install Redmine, mySQL and Apache 1 apt-get install redmine-mysql redmine mysql-server apache2 Link the redmine code to /var/www/redmine : ln -s /usr/share/redmine/public /var/www/redmine Install the apache2 passenger and fastcgi apt-get install libapache2-mod-passenger libapache2-mod-fastcgi Add this line to /etc/apache2/mods-available/passenger.conf (inside the IfModule directive): PassengerDefaultUser www-data Edit /etc/apache2/sites-enabled/000-default and add after the two first <directory> directives: RailsBaseURI /redmine PassengerResolveSymlinksInDocumentRoot on Options Indexes ExecCGI FollowSymLinks In /var/www/redmine/ , create the file .htaccess , with exactly this content: RewriteEngine On RewriteRule ^(.*)$ dispatch.fcgi [QSA,L] Restart apache: apache2ctl restart Credit : 1

As some ISPs are blocking outgoing mail from home smtp server, we have to use a relay. smtp.gmail.com is a good choice. Here are the steps I've followed in order to configure postfix on ubuntu 10.10 to use gmail as a relay : Install postfix Choose Internet Site and keep the proposed next option aptitude install postfix configure postfix cd /etc/postfix nano main.cf add the following lines at the end of the file : relayhost = [smtp.gmail.com]:587 smtp_use_tls = yes smtp_tls_CAfile = /etc/postfix/cacert.pem smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/sasl/passwd smtp_sasl_security_options = noanonymous (there is no need to comment out the same options that can be present before in the file as only the last ones are used) create the file passwd cd /etc/postfix/sasl/ nano /etc/postfix/sasl/passwd insert this line, changing your own logon information [smtp.gmail.com]:587 yourname@gmail.com:yourpassword generate a db file that postfix can re...