A server stack is the collection of software that forms the operational infrastructure on a given machine. In a computing context, a stack is an ordered pile. A server stack is one type of solution stack — an ordered selection of software that makes it possible to complete a particular task. Like in this post about Why can I change the the reserved blocks on a read only mounted ext4 filesystem? was one problem in server stack that need for a solution. Below are some tips in manage your linux server when you find problem about linux, ext4, ubuntu-20.04, read-only, .
I would have expected an error, sorry FS is read-only, but it is possible. This is unexpected & counter intuitive is there a reason?
Linux files 5.11.0-27-generic #29~20.04.1-Ubuntu SMP Wed Aug 11 15:58:17 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
files@files:/mnt/disk$ mount | grep /mnt/disk/005
/dev/sdh on /mnt/disk/005 type ext4 (ro,nosuid,nodev,noexec,relatime,user)
files@files:/mnt/disk$ df /mnt/disk/005/
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdh 7751367424 7332824836 27824876 100% /mnt/disk/005
files@files:/mnt/disk$ sudo tune2fs -r 0 /dev/sdh
tune2fs 1.45.5 (07-Jan-2020)
Setting reserved blocks count to 0
files@files:/mnt/disk$ df /mnt/disk/005/
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdh 7751367424 7332824836 418526204 95% /mnt/disk/005
files@files:/mnt/disk$
tune2fs never needed the filesystem to be mounted to operate. As you can see in the command, you pass a block device node (/dev/sdh) as an argument to it, not a mountpoint (/mnt/disk/005). It’s similar to resize2fs and e2label.
