ubiquity migration assistant did not unmount other Linux volumes

I finally discovered where ubiquity failed. When I finished "Who are you?" These are the mount points

ubuntu@ubuntu:~$ df
Filesystem 1K-blocks Used Available Use% Mounted on
aufs 771516 40672 730844 6% /
none 764808 284 764524 1% /dev
/dev/sr0 722346 722346 0 100% /cdrom
/dev/loop0 687872 687872 0 100% /rofs
none 771516 164 771352 1% /dev/shm
tmpfs 771516 44 771472 1% /tmp
none 771516 88 771428 1% /var/run
none 771516 4 771512 1% /var/lock
/dev/sda10 21413452 634204 19691504 4% /target

But if I click on Forward, then suddenly ubiquity mounts not selected Linux partitions to the same target diectory, which causes ubiquity to fail.

ubuntu@ubuntu:~$ df
Filesystem 1K-blocks Used Available Use% Mounted on
aufs 771516 40700 730816 6% /
none 764808 284 764524 1% /dev
/dev/sr0 722346 722346 0 100% /cdrom
/dev/loop0 687872 687872 0 100% /rofs
none 771516 164 771352 1% /dev/shm
tmpfs 771516 44 771472 1% /tmp
none 771516 88 771428 1% /var/run
none 771516 4 771512 1% /var/lock
/dev/sda10 48027996 2903708 42684608 7% /target
/dev/sda6 48027996 2903708 42684608 7% /target
/dev/sda8 48027996 2903708 42684608 7% /target
ubuntu@ubuntu:~$

On /dev/sda6 is Ubuntu 10.04.1 installed. On /dev/sda8 is Ubuntu 10.10 installed.

I found a workaround. When I manually selected partiton /dev/sda10 as root partition formatted as EXT4 and click on Forward and I wait for the "Ready when you are" dialog. Then I did the rest of the steps. Then again if I click by "Who are you?" on Forward ubiquity still mount other Linux partitions to the same target directory. But this time I did manually umounted /dev/sda6 and /dev/sda8

sudo umount /dev/sda8
sudo umount /dev/sda6

So only /dev/sda10 is mounted to the target directory. After that I was able to finish the installation with succes.

It seems the installation error is caused by the ubiquity migration assistant. With the migration assistant disabled, I am able to install the natty desktop i386 without any problems. The ubiquity migration assistant bug occurs still with today's build.

This issue is also mentioned in https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/570845

Me too.

I have been suffering from this bug since first alpha !
Just now I managed to install Ubuntu 11.04 !
I would like to say that the problem is even though I select nothing to migrate it still trying to migrate !

I have Ubuntu 10.10 on a partition and the Home on another (you know that the beauty of Ubuntu)

I finally get rid of it by deleting Ubuntu 10.10 !

And Now I am going to reinstall it again !

Thank you.

I had this same problem using both Natty Alpha 3 and the daily build from 3-21-2011.

The solution posted by jolo in Post #2 worked - i.e. waiting at the personal info page and then unmounting all partitions but the installation partition.

When I checked, every Ubuntu release I had installed was mounted to /target (lucid, maverick, lucid /home, maverick /boot) and I couldn't install until I unmounted all from /target except the real /target partition.

Note: I use the same name, username, computer name and password on all installs if that might have any bearing on the matter.

Testing install of new Natty 11.04 downloaded today and yesterdays current
daily build dated 04/27/2011.

Just tried another fresh install from flash drive and had the same problem with
current Natty build. I have two working Natty versions on my laptop but tried
another install just to see how it would go. Like drs305 I have numerous partitions
with (Lucid, Xubuntu 10.04, 2 Natty version fully updated from December and Maverick.
All were targeted and I could not manually unmount them.

I tried the install a couple times going from different angles to no positive effect with
different flash drives and different partitions. Finally I install Maverick 10.10
again on the same partition with the same flash drive. (all good)
It appears the ubiquity migration assistant does not work properly for me.

I also use the same sign-in name and password. However I did try with a
different user name and password same results.

This affects Ubuntu 11.04 Beta1,Beta2 and the final release. (all 64 bit versions). Did not face this problem in earlier versions of Ubuntu.

I have the exact same problem here. Did not select anything to migrate, but migration assistant still runs anyway. Like Greg, I have multiple installations (Maverick 64 bit, Debian 32 bit, Hardy 32 bit, GRUB2 under Maverick's control).

Migration assistant displays an error dialog saying that it could not unmount some partition. Used mount command and found that many partitions were mounted under /target and one of them (/dev/sda8) was mounted under /target/home. Could not manually unmount any of them including /dev/sda8.

If I choose 'Continue', the same dialog is shown again. 'Go back' just skips the remaining installation steps and says that the installation is over (even though it's not).

IMO this should be atleast Medium if not High since even installation is not possible.

I do confirm this problem. The installation doesn't finish even when Ubuntu installer says it does. I receive a grub problem when trying to boot.

I need to specify a /home partition but when I do so migration-assistant runs then everything fails.

I solved the issue in a different way specific to my case.

After installation failed as reported in this bug, I just continued using the LiveCD and ran the Installer from the Desktop.

But, before starting installation, I noticed before that Ubiquity was thinking that my old /home partition had installed Ubuntu 11.04, and it was because there was an 'etc' directory I placed there for an eventual backup.

So, I think Ubiquity detected my /home partition as a target installation since it had a '/etc' directory inside. So I just renamed my 'etc' directory to 'etc.bk' and continued the rest of the installation without problems.

Neither ubiquity or migration assist should try to read other partitions than the one we tell it to! I don't even see any migration options to check.
I've been hours here trying to solve this. Now trying with ubiquity --desktop --no-migration-assistant --only gtk_ui.
Natty Final 64bits.

Nope... same thinig:
May 3 02:59:01 ubuntu migration-assistant: error: Failed to mount /dev/sda1 and the infamous Error window pops up.

sda1 is a RAID member! (I've tried without mdadm installed, so no mounted RAIDs, and now I'm trying with mdadm installed, RAID assembled AND mounted)

Even without checking the option to download during installation, and with installation cmoplete with the Restart Now button, I still see plugininstall.py working and downloading stuff... very strange. Guess we have to wait till syslog gets quiet before reboot... grub was installed like 30 seconds after I got the Restart Now button.

Got it working. I'm thinking the forking of that migration error might be giving us a Restart Now button too early, before the whole install finishes, specially grub installation.

Interestingly, I install Xubuntu 11.04 on the same partition without any problems. Since I was just testing the Ubiquity and Migration assistant anyway. I kind of like the simple Xubuntu version for a change from testing Unity.

Okay, here I am again amending this bug. Tired to install Oneiric 32 bit from current daily build yesterday. Had the same issue with the migration assistant as when trying to install Natty from live USB. I have multiple distros in 7 partitions on this laptop and never selected to migrate anything as I can do that anytime after I get a clean install, but the ubiquity migration assistant targets just about all my partitions even though I do not choose any and I can't umount them manually. I have also installed Fedora 15 with Gnome 3 since the last message above without a hitch. It surprises me that more multi-booting users do not have this problem. Anyway, I was able to install Oneiric from the alternate iso today and have it running for testing FINALLY

This bug still exists in 11.10. I use a Thinkpad with a Windows and two existing Ubuntu Partitions. Both are mounted to /target and are not manually unmountable.

natty have reached EOL now