Computers and Complexity

Computers are complex tools. Sometimes too complex.

I wanted to verify something in a virtual machine (VM). At home, walking to the office is a 20 second adventure, but the convenience of technology is tempting. With my laptop I connected to the office computer with SSH. I launched the virtual machine in headless mode.

After confirming the VM was running, I attempted to connect to the VM from the laptop using Remmina.

Except nothing worked. I've connected this way many times.

Same results using the rdesktop command.

What was broken now? Much weeping and gnashing of teeth pursued.

Eventually I found the culprit.

The RDP interface no longer functioned because I had changed the VirtualBox remote desktop extension (VRDE) to VNC. According to my shell history in backups, about six months ago.

There are two modes for VRDE: RDP and VNC. To toggle the VRDE:

    vboxmanage setproperty vrdeextpack VNC
    vboxmanage setproperty vrdeextpack "Oracle VM VirtualBox Extension Pack"

Nothing I tried provided any feedback or clues about the root cause of the failure. Only while painfully poking around the web looking for help did I run across a vague comment that helped ring the proverbial bell.

Resolving problems like this is gratifying, but would be more gratifying if such problems never surfaced. Even more gratifying if developers wrote helpful error messages.

Posted: Category: Usability Tagged: General

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