How to expand the overlayfs on a "live" install

I have made a rescue USB drive from Tumbleweed. I installed it on the drive using rufus on a windows PC. All well and it boots on legacy systems too.

However the drive is only 2GB and with the base system taking about 1GB leaving the 1GB for the overlayfs to reflect changes that I have made. I have now run out of space …

Again using rufus I made a disk image of my 2GB USB drive and then installed it on a 125GB USB drive. It all boots fine but the overlayfs is still essentially full. What’s the correct procedure for expanding the overlayfs, that assumes there is one? Or is it just a simple case of using Gpartd to expand it?

Thanks.

Hi
What is the file system in use?

For btrfs all that is needed is;


btrfs filesystem resize max /

It’s called overlayfs and appears to be part of the FUSE system.

I had never come across it until today.

Rufus has multiple modes of operation so saying “I used rufus” tells nothing.

overlayfs is virtual filesytsem which links two real filesystems, “lower” one (usually read-only) and “upper” one (usually read-write). You have read-only lower filesystem and overlayfs allows to store modifications to it on separate upper filesystem, “merging” both of them. You cannot “expand overlayfs”.

You need to expand upper filesystem that is used to store modifications. Live images normally do it automatically on first boot, expanding upper filesystem to the maximum possible size. Show output of

fdisk -l
df -h
cat /proc/self/mountinfo

in live system, to see what actual partitions are used.

Thanks that’s a great explanation of how the overlayfs actually works. As such it looks like I should just be able to manipulate upper file system as I would any other offline.

Yet another example:

**erlangen:~ #** lsblk -f /dev/sdd 
NAME   FSTYPE  FSVER            LABEL                       UUID                                 FSAVAIL FSUSE% MOUNTPOINT 
sdd    iso9660 Joliet Extension openSUSE_Leap_15.2_KDE_Live 2020-07-28-11-03-09-00                               
├─sdd1 iso9660 Joliet Extension openSUSE_Leap_15.2_KDE_Live 2020-07-28-11-03-09-00                     0   100% /run/media/karl/openSUSE_Leap_15.2_KDE_Live 
├─sdd2 vfat    FAT16            BOOT                        FA08-7FDF                                            
└─sdd3 ext4    1.0              cow                         2b072de7-2703-4d8c-af4c-b4ad9561c27b   50.9G     6% /run/media/karl/cow 
**erlangen:~ #**

Usage of cow grows as changes are made.