six degrees of freedom

  • Open VNC virt-viewer (.vv) files on macOS

    I tried to use virt-viewer from homebrew but it didn’t work properly. Instead I decided to write an Automator App that reads the contents of the .vv file and opens the macOS built-in VNC viewer. Create a new Automator Application, and add the “Run Shell Script” action and choose to pass input as arguments. Select […]

  • This copy of the Install macOS Catalina application is damaged

    I recently needed to reinstall macOS via USB stick on a laptop that has not been used for a while. I was able to boot from the USB, but when running the installer I was greeted with the “This copy of the Install macOS Catalina application is damaged…” message. Curiously, the same USB stick worked […]

  • FreeRADIUS two factor authentication (OTP and Password)

    MultiOTP is a tool to verify one-time passwords from hardware or software HOTP or TOTP devices. In the README they describe how to set up FreeRADIUS for OTP verification. By default, MultiOTP requires entering a 4 digit personal PIN plus the token (usually 6 digits). For better security in multi-factor authentication (MFA), it’s a good […]

  • Nomachine reports “ERROR: Unsupported operating system ‘linux’”

    I’m trying to install Nomachine NX Enterprise Server on Ubuntu, and the installation of the .deb package fails with: NX> 704 ERROR: Unsupported operating system ‘linux’ After looking at the install script, I found a simple solution: sudo touch /etc/debian_version

  • Two-factor authentication for mySQL users

    I want to authenticate mySQL users with a password and a token on Ubuntu, so I figured out a way to do this using MariaDB, PAM and Google Authenticator. First we need a plugin for mySQL that can authenticate users against PAM. The non-free enterprise version of mySQL has authentication_pam.so. I’m not an Enterprise customer, so […]

  • Disable annoying pop-up messages in VirtualBox

    Run from command line: VBoxManage setextradata global GUI/SuppressMessages “all”

  • 3G USB stick Huawei E169/E620/E800 HSDPA in Linux

    Simply install the “wvdial” package and edit /etc/wvdial.conf: [Dialer Defaults] Phone = *99***1# Username = username Password = password Stupid Mode = 1 Dial Command = ATDT [Dialer hsdpa] Modem = /dev/ttyUSB0 Baud = 460800 Init2 = ATZ Init3 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 ISDN = 0 Modem Type = Analog Modem […]

  • CurlFTPfs: 95 Operation not supported

    I’ve been using curlFTPfs with rdiff-backup and ran across this problem when creating the remote backup log file: ftpfs: operation ftpfs_open failed because Operation not supported unique: 889, error: -95 (Operation not supported), outsize: 16 The curlFTPfs author says: “Be aware that some applications might not be able to “save” files on curlftpfs from 0.9.2 […]

  • OpenStack “backing file” cleanup script

    Sometimes OpenStack leaves the “backing file” of the sparse root filesystem behind after a VM is destroyed. Those files are located in /var/lib/nova/instances/_base/ and can use up hundreds of GB. To find out which of those backing files are orphans and delete them, someone has posted a script, which I slightly improved: #!/bin/sh cd /var/lib/nova/instances […]

  • How to create a bootable volume in Openstack Folsom

    Wouldn’t it be nice to have the root filesystem of your Openstack VM inside a volume? This way you could install a lot of packages on the root partition without spreading the files over several volumes. You could take a snapshot of the entire system (OS & data) and boot right off it. Openstack Folsom […]

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