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I'm trying to create a ramdisk inside a VM. I think I have the ability to use tmpfs, because it is Ubuntu 10.04 which comes with kernel > 2.6. I added this to /etc/fstab:

none /mnt/test tmpfs defaults,user,size=1G,mode=0777 0 0

Then why I try to mount /mnt/test, I get:

mount: wrong fs type, bad option, bad superblock on none,
       missing codepage or helper program, or other error
       (for several filesystems (e.g. nfs, cifs) you might
       need a /sbin/mount.<type> helper program)
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

What to do ?

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Does mount tmpfs /mnt -t tmpfs -o size=1G work? – Marco Jul 19 '12 at 9:58
yes, solved it, thanks. But why ? (the -o option isn't necessary, but the rest is). – jlock Jul 19 '12 at 11:04

Unfortunately the Lucid man page doesn't properly tell you the first field for tmpfs.

Replace 'none' with 'tmpfs'.

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