USB drive not mounted and read-only error

[Markfree]

Hey everyone.

I wanted to share something I noticed today regarding the RT-AX86U router.
It caught my attention that AdGuard wasn't running, so I decided to investigate further. Upon checking the router, I discovered that Entware was not mounted. To my surprise, the USB drive itself was not mounted either, seemingly out of nowhere.

The syslog file revealed a series of error lines related to this issue.

May 31 09:57:06 amtm disk-check: Probing 'ext4' on device /dev/sda1
May 31 09:57:06 amtm disk-check: Running disk check v3.1, with command 'e2fsck -p' on /dev/sda1
May 31 09:57:06 amtm disk-check: Disk check done on /dev/sda1
May 31 09:57:06 hotplug: USB /dev/sda1(ext) failed to mount!
May 31 09:57:06 kernel: EXT4-fs (sda1): couldn't mount as ext3 due to feature incompatibilities
May 31 09:57:06 kernel: EXT4-fs (sda1): INFO: recovery required on readonly filesystem
May 31 09:57:06 kernel: EXT4-fs (sda1): write access unavailable, cannot proceed
May 31 09:57:06 kernel: EXT4-fs (sda1): couldn't mount as ext3 due to feature incompatibilities
May 31 09:57:06 kernel: EXT4-fs (sda1): couldn't mount as ext2 due to feature incompatibilities
May 31 09:57:06 kernel: EXT4-fs (sda1): INFO: recovery required on readonly filesystem
May 31 09:57:06 kernel: EXT4-fs (sda1): write access unavailable, cannot proceed
May 31 09:57:06 kernel: tfat: fail_safe is enabled
May 31 09:57:06 kernel: tfat: fail_safe is enabled
May 31 09:57:06 kernel: tfat: fail_safe is enabled
May 31 09:57:06 kernel: tntfs info (device sda1, pid 5009): ntfs_fill_super(): fail_safe is enabled.
May 31 09:57:06 hotplug: USB /dev/sda1(ext) failed to mount!
May 31 09:57:06 kernel: EXT4-fs (sda1): couldn't mount as ext3 due to feature incompatibilities
May 31 09:57:06 kernel: EXT4-fs (sda1): INFO: recovery required on readonly filesystem
May 31 09:57:06 kernel: EXT4-fs (sda1): write access unavailable, cannot proceed
May 31 09:57:06 kernel: EXT4-fs (sda1): couldn't mount as ext3 due to feature incompatibilities
May 31 09:57:07 kernel: EXT4-fs (sda1): couldn't mount as ext2 due to feature incompatibilities
May 31 09:57:07 kernel: EXT4-fs (sda1): INFO: recovery required on readonly filesystem
May 31 09:57:07 kernel: EXT4-fs (sda1): write access unavailable, cannot proceed
May 31 09:57:07 kernel: tfat: fail_safe is enabled
May 31 09:57:07 kernel: tfat: fail_safe is enabled
May 31 09:57:07 kernel: tfat: fail_safe is enabled
May 31 09:57:07 kernel: tntfs info (device sda1, pid 5044): ntfs_fill_super(): fail_safe is enabled.

Upon attempting to check the drive, I discovered that it had become read-only for some unknown reason. I'm puzzled about what might have caused this sudden change.

/tmp/home/root# e2fsck -p /dev/sda1
e2fsck: Read-only file system while trying to open /dev/sda1
Disk write-protected; use the -n option to do a read-only
check of the device.

/tmp/home/root# e2fsck -n /dev/sda1
e2fsck 1.45.6 (20-Mar-2020)
Warning: skipping journal recovery because doing a read-only filesystem check.
entware: clean, 3192/940240 files, 394695/3753980 blocks

/tmp/home/root# fdisk -l /dev/sda1
Disk /dev/sda1: 15.3 GB, 15376302080 bytes
64 heads, 32 sectors/track, 14663 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Disk /dev/sda1 doesn't contain a valid partition table

/tmp/home/root# mount -vv /dev/sda1 /tmp/test/
mount: mount('/dev/sda1','/tmp/test/','vfat',0x00008000,'(null)'):-1: No such device
mount: mount('/dev/sda1','/tmp/test/','ext3',0x00008000,'(null)'):-1: Read-only file system
mount: mount('/dev/sda1','/tmp/test/','ext3',0x00008001,'(null)'):-1: Invalid argument
mount: mount('/dev/sda1','/tmp/test/','ext4',0x00008000,'(null)'):-1: Read-only file system
mount: mount('/dev/sda1','/tmp/test/','ext4',0x00008001,'(null)'):-1: Invalid argument
mount: mount('/dev/sda1','/tmp/test/','ext3',0x00008000,'(null)'):-1: Read-only file system
mount: mount('/dev/sda1','/tmp/test/','ext3',0x00008001,'(null)'):-1: Invalid argument
mount: mount('/dev/sda1','/tmp/test/','ext2',0x00008000,'(null)'):-1: Read-only file system
mount: mount('/dev/sda1','/tmp/test/','ext2',0x00008001,'(null)'):-1: Invalid argument
mount: mount('/dev/sda1','/tmp/test/','ext4',0x00008000,'(null)'):-1: Read-only file system
mount: mount('/dev/sda1','/tmp/test/','ext4',0x00008001,'(null)'):-1: Invalid argument

$ sudo tune2fs -l /dev/sdb1 | grep features
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize

AMTM's disk check log shows that yesterday it was fine. Today, not anymore.

Tue May 30 04:01:47 GMT 2023 Probing 'ext4' on device /dev/sda1
 Running disk check v3.1, with command 'e2fsck -p' on /dev/sda1
 entware: clean, 3192/940240 files, 394695/3753980 blocks
 Tue May 30 04:01:47 GMT 2023 Disk check done on /dev/sda1


 Wed May 31 04:01:53 GMT 2023 Probing 'ext4' on device /dev/sda1
 Running disk check v3.1, with command 'e2fsck -p' on /dev/sda1
 e2fsck: Read-only file system while trying to open /dev/sda1
 Disk write-protected; use the -n option to do a read-only
 check of the device.
 Wed May 31 04:01:53 GMT 2023 Disk check done on /dev/sda1

Do any of you have any ideas or suggestions on how to resolve this situation?
Thank you in advance for your help.

 

[L&LD]

Cheap USB drives. Known issue. They die.

Get an external enclosure and put in an SSD (256GB or larger).

Start from scratch and set up amtm and all other scripts again.

 

[Markfree]

Cheap USB drives. Known issue. They die.
Get an external enclosure and put in an SSD (256GB or larger).
Start from scratch and set up amtm and all other scripts again.

Yeah, it seems that way.
It held for a while actually. About 3 years running 24/7.
It had a good life.

 

[ColinTaylor]

Same flash drives (like SanDisk) go into read-only mode to protect the data when it thinks it's about to fail. Unfortunately there's no way to force it back to read/write mode when this happens (see Sandisk's website and forums). You can confirm whether this is the problem by plugging into a PC and seeing if it can format it.