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I've got various RAID 1 & 0 (MDADM) arrays mounted in /media/ via fstab but I'm coming into trouble creating/deleting files from some of these volumes from the GUI and programs, it's as if they are mount read-only. My default fstab mount options for non home/root arrays is:

UUID="xxx"  /media/xxx  ext4    noatime,data=writeback,errors=remount-ro    0   1

A typical bootup mount reads as:

md6: detected capacity change from 0 to 25999966208
[    4.112397]  md6: unknown partition table
[    4.154724] md: bind<sdc9>
[    4.173584] md/raid1:md18: active with 2 out of 2 mirrors
[    4.173651] md18: detected capacity change from 0 to 80967303168
[    4.215755]  md18: unknown partition table
[    4.303747] md: bind<sdc8>
[    4.335634] md/raid0:md15: md_size is 156249856 sectors.
[    4.335685] md: RAID0 configuration for md15 - 1 zone
[    4.335735] md: zone0=[sdc8/sdd8]
[    4.335876]       zone-offset=         0KB, device-offset=         0KB, size=  78124928KB

There's no mention of errors or readonly here in dmesg. I've tried removing the ro option but this makes not difference. What can I try next?

I have added write permissions to the group as a workaround (sudo chmod go+rw /media/xxx) but I'm not sure why this isn't available by default as it would be normally, and perhaps adding these permissions is a security risk.

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