Where is the upper layer of the live cd image overlayfs root filesystem stored?
When I run the live image (Ubuntu 18.04), it shows the root filesystem being an overlay with the squashfs image (/cdrom/casper/filesystem.squashfs, containing the main data) as lower layer, and /cow/upper as upper layer. But /cow is not visible anymore as it is hidden by the overlay mounted on root.
Where (on what device) does the upper layer live? Is it accessible somewhere or is it a memory-only device?
mount live-environment overlayfs
asked Dec 21 at 12:33
JanKanis
26629
add a comment |
When I run the live image (Ubuntu 18.04), it shows the root filesystem being an overlay with the squashfs image (/cdrom/casper/filesystem.squashfs, containing the main data) as lower layer, and /cow/upper as upper layer. But /cow is not visible anymore as it is hidden by the overlay mounted on root.
Where (on what device) does the upper layer live? Is it accessible somewhere or is it a memory-only device?
mount live-environment overlayfs
asked Dec 21 at 12:33
JanKanis
26629
Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50
add a comment |
When I run the live image (Ubuntu 18.04), it shows the root filesystem being an overlay with the squashfs image (/cdrom/casper/filesystem.squashfs, containing the main data) as lower layer, and /cow/upper as upper layer. But /cow is not visible anymore as it is hidden by the overlay mounted on root.
Where (on what device) does the upper layer live? Is it accessible somewhere or is it a memory-only device?
mount live-environment overlayfs
asked Dec 21 at 12:33
JanKanis
26629
When I run the live image (Ubuntu 18.04), it shows the root filesystem being an overlay with the squashfs image (/cdrom/casper/filesystem.squashfs, containing the main data) as lower layer, and /cow/upper as upper layer. But /cow is not visible anymore as it is hidden by the overlay mounted on root.
Where (on what device) does the upper layer live? Is it accessible somewhere or is it a memory-only device?
mount live-environment overlayfs
mount live-environment overlayfs
asked Dec 21 at 12:33
JanKanis
26629
asked Dec 21 at 12:33
JanKanis
26629
edited Dec 21 at 12:44
asked Dec 21 at 12:33
JanKanis
26629
asked Dec 21 at 12:33
JanKanis
26629
asked Dec 21 at 12:33
JanKanis
26629
26629
Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50
add a comment |
Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50
Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50
Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50
add a comment |
1 Answer
1
active
oldest
votes
COW stands for copy-on-write, In the case of live media it refers to the changes that are made to the live environment. It is accessible if you boot live iso in persistence mode, in that case it is written to the drive, folder or casper-rw container file you specify. But if persistence mode is not enabled it is just a memory only device.
There are many articles available on askubuntu regarding persistence.
answered Dec 21 at 13:51
harshit
1049
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
COW stands for copy-on-write, In the case of live media it refers to the changes that are made to the live environment. It is accessible if you boot live iso in persistence mode, in that case it is written to the drive, folder or casper-rw container file you specify. But if persistence mode is not enabled it is just a memory only device.
There are many articles available on askubuntu regarding persistence.
answered Dec 21 at 13:51
harshit
1049
add a comment |
COW stands for copy-on-write, In the case of live media it refers to the changes that are made to the live environment. It is accessible if you boot live iso in persistence mode, in that case it is written to the drive, folder or casper-rw container file you specify. But if persistence mode is not enabled it is just a memory only device.
There are many articles available on askubuntu regarding persistence.
answered Dec 21 at 13:51
harshit
1049
add a comment |
COW stands for copy-on-write, In the case of live media it refers to the changes that are made to the live environment. It is accessible if you boot live iso in persistence mode, in that case it is written to the drive, folder or casper-rw container file you specify. But if persistence mode is not enabled it is just a memory only device.
There are many articles available on askubuntu regarding persistence.
answered Dec 21 at 13:51
harshit
1049
COW stands for copy-on-write, In the case of live media it refers to the changes that are made to the live environment. It is accessible if you boot live iso in persistence mode, in that case it is written to the drive, folder or casper-rw container file you specify. But if persistence mode is not enabled it is just a memory only device.
There are many articles available on askubuntu regarding persistence.
answered Dec 21 at 13:51
harshit
1049
answered Dec 21 at 13:51
harshit
1049
answered Dec 21 at 13:51
harshit
1049
answered Dec 21 at 13:51
harshit
1049
1049
add a comment |
add a comment |
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Is there any way to access it? (Just for the fun of it, as it is lost on reboot)
– JanKanis
Dec 21 at 12:50