Basically my root (
/) ext4 partition keeps being mounted as read-only when I apply internal journaling feature. I understand that this should be default, but today I had been trying to apply external journals to ramdisk for each of my ext4 partitions since I am using an SSD and wanted to obtain maximum performance from it (which journaling impedes: http://raid6.com.au/posts/fs_ext4_external_journal/). I'd gotten myself into a mess when after applying external journals to ramdisk, I rebooted my machine to find that it would no longer boot since the ramdisk's were not persistent and the ext4 partitions were trying to load/apply external journals at ramdisks that no longer existed so I then had to "rescue" the installation with the CentOS 7 Live CD "rescue" feature.
So basically, I can no longer apply the internal journal on my root partition. I have corrected it on my other partitions (which strangely enough only
/opt will unmount without being "busy"). IS there a way to fix this? I'd like to have internal journaling on while I properly get round implementing journaling to external ramdisk.
I am trying to turn back on the internal journaling feature of the ext4 partition with:
tune2fs -O has_journal /dev/sda3
But when rebooting, the root partition mounts as read-only, and I cannot unmount it and remount as
rw. So I have to turn it off with:
tune2fs -O ^has_journal /dev/sda3
All feedback welcome.