Virtual Disc Size and Utilisation

[wcndave]

I created an Ubuntu guest with 8GB "Normal" disc size, which I believe is exandable (if that's what normal allows), but anyway 8GB seems plenty for a Linux host, however the disk is actually using 4GB and reporting itself as "full".

I can't see how to expand it, and I can't log in to the machine now...

I am not allowed to post images..

i.imgur / 7HrFXAm.jpg

Any ideas why it's only using half the space I allocated.

[mpack]

FAQ.

E.g. viewtopic.php?f=1&t=29838

Moved to "Linux Guests" since the question asked is really about understanding how Linux works.