Small snap loop devices visible in gnome-disk-utility OR what is the function of snap ubuntu-core
Solution 1
Each individual snap is a read-only squashfs filesystem image. In order to access files within these images, snapd
mounts the images, one for each installed snap version, inside /snap
.
This list of mounted loop devices thus effectively includes the snaps you have installed, and is part of the normal operation of snapd
. You should not attempt remove them. If you really don't want them there at all, then you can remove the corresponding snaps.
Various utilities are designed to show you all mounted filesystems, including loopback ones, which is why you see them. snapd
is the first common daemon I've seen to maintain a large and variable set of loopback mounts in this way, which admittedly does hamper the UI of these utilities. Perhaps eventually we'll see these utilities hide loopback mounts by default.
Solution 2
You can remove old core by execute
sudo snap remove core --revision <number>
manually.
Solution 3
If you don't use snaps it than just uninstall them as you did. Ubuntu core is the snap that the others snaps need to run. Visiblity of snaps in gnome-disk-utility is probably not wanted but it's a side effect of how snaps are working.
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dufte
Updated on September 18, 2022Comments
-
dufte over 1 year
I just realized using
gnome-disk-utility
(3.18.3.1) that my 16.04 installation is featuring several small loop devices.In detail:
- 78 MB Loop Device (/var/lib/snapd/sn_ntu-core_352.snap -> /dev/loop0)
- 76 MB Loop Device (/var/lib/snapd/sn_ntu-core_216.snap -> /dev/loop1)
- 79 MB Loop Device (/var/lib/snapd/sn_ntu-core_423.snap -> /dev/loop2)
- 705 KB Loop Device (/var/lib/snapd/snaps/tpad_12.snap -> /dev/loop3)
- 684 KB Loop Device (/var/lib/snapd/snaps/tpad_11.snap -> /dev/loop5)
- 705 KB Loop Device (/var/lib/snapd/snaps/tpad_13.snap -> /dev/loop6)
Image showing
gnome-disk-utility
My questions are as follows:
- What are those loop devices used for?
- Is that an expected behaviour in 16.04?
- Can I remove them? And if so - how (just by unmounting)?
- Is there any risk in removing the 2 installed snaps mentioned below (tpad and ubuntu-core)
UPDATE
Installed snaps
According to
snap list
I do have- tpad (1.8.1)
- ubuntu-core (16.04.1)
installed. I remember I did tinker with snaps for a short time when I realized this option - but am pretty unsure if I installed those 2 snaps - or if they are pre-/auto-installed.
tpad is a Terminal text editor with GUI-like user interface I did install manually, as I don't use it I removed it now via
sudo snap remove tpad
. As a result the 2 loop devices pointing to tpad are gone ingnome-disk-utility
.So - at the current point I am still having 1 snap installed called
ubuntu-core
and I don't know what it is used for. The summary of this particular snap isThe ubuntu-core OS snap
-
d a i s y over 7 yearsThis might be a bug
-
Pablo Bianchi about 7 yearsThis might be this bug. Snapd left all those ugly loop devices. Also there at every
df
. -
becko almost 7 years@PabloBianchi Are they taking up actual HD space? Even if I unnstall the snap package?
-
Erik Bennett about 5 years@PabloBianchi That bug is marked as WONTFIX. Too bad, since it's very tacky (Neglected and in a state of disrepair).
-
dufte over 7 yearsThe snap ubuntu-core is not removeable using
sudo snap remove ubuntu-core
->error: cannot remove "ubuntu-core": snap "ubuntu-core" is not removable
. I removedsnapd
package as i am not going to usesnap
further, but the 3 snap loop devices in disk-utility are still remaining. -
Ads20000 over 6 yearsThis wouldn't solve the problem in this case, sorry!
-
zwol almost 5 yearsThe above may have been a bug that is now fixed: I just removed
snapd
from a fresh install of Ubuntu 19.04 (server) and thecore
snap was removed as a side-effect. -
Peter Krauss almost 5 yearsHow to list the labels
<number>
? Thedf
"/dev/loop2" is number 2?