I have a buildroot generated embedded linux system (x-86 geode processor) using an initramfs but with
/etc mounted onto a compact flash device using the default mount options specified in
fstab. My filesystems are ext3.
I run a controller application on this system which generates some custom activity logging from time to time to files created on the
/var partition. Recently one of my embedded devices was reporting that it could not open the log file as the /var partition was a read only partition. I verified with using
mount. My question is how on earth could this happen? My controller application certainly does not do this, but are there any other processes that run on a linux system that could request a remount of /var as read only?
My devices do run in noisy industrial environments so is it possible that this could be come kind of system corruption due to EM interference?
This has never happened before over several hundred hours of testing but it is a critical error that I need to find a cause for so any suggestions as to what could have caused this or how to ascertain what caused it are very welcome.
EDIT In light of the criticism this question has received, I include the relevant line of fstab for mounting the /var partition:
/dev/sda3 /var ext3 defaults 0 3
and the line within the
inittab function responsible for mounting
also here is the output line from
/proc/mounts relevant to
/dev/sda3 /var ext3 rw,relatime,errors=continue,user_xattr,scl,barrier=1,data=writeback 0 0
I should probably also mention that the system uses
busybox init system.