# Can't mount ext filesystem because of unsupported features

## ryan.n

So I have a computer with Gentoo and a few hard drives to store backups/music/etc.  I haven't really done anything to it in awhile and when I went searching for files on one of the hard drives, I noticed one of the partitions weren't mounted.  Here's the fstab for the drive:

```

/dev/sdb1               /media/music    ext3            noatime         0 0

/dev/sdb2               /media/upload   ext3            noatime         0 0

/dev/sdb3               /media/applications ext3        noatime         0 0

/dev/sdb5               /media/television-2 ext3        noatime         0 0

/dev/sdb6               /media/other    ext3            noatime         0 0

```

All the partitions are mounted except for /dev/sdb6.  So I run:

```

# mount /media/other

mount: wrong fs type, bad option, bad superblock on /dev/sdb6,

       missing codepage or helper program, or other error

       In some cases useful info is found in syslog - try

       dmesg | tail  or so

```

```

# dmesg|tail

EXT3-fs: sdb6: couldn't mount because of unsupported optional features (1d0000).

```

```

# e2fsck /dev/sdb6

e2fsck 1.40.9 (27-Apr-2008)

/dev/sdb6 has unsupported feature(s): FEATURE_I16 FEATURE_I18 FEATURE_I19 FEATURE_I20

e2fsck: Get a newer version of e2fsck!

```

If I comment out the line in /dev/fstab and run

```

# mount /dev/sdb6 /media/other

mount: unknown filesystem type 'ext4'

```

I have no idea whats going on with this partition.  I don't know how long its been messed up since I haven't needed to access anything from there in a while (probably over a year or 2).  I looked at my kernel options but everything seems to be checked off for ext3 support (and all partitions on the drive had mke2fs ran on it at the same time, with the same options so I don't know why only that one would have 'unsupported feature' errors).

Any help would be MUCH appreciated.  I have a lot of original pictures/videos on there from some class projects I did with my friends in high school and I will be really bummed if they're gone

----------

## platojones

Looks like it was converted to and ext4 filesystem.  You'll need a kernel with ext4 support (and e2fsprogs) to mount it.

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## piponazo

Hi!. I have a similar problem. In my case, all my partitions are mounted correctly, but in the kernel messages is shown:

```
$ sudo dmesg | grep sda6

[    0.000000] Command line: root=/dev/sda6 

[    0.000000] Kernel command line: root=/dev/sda6 

[    1.043426]  sda: sda1 sda2 < sda5 sda6<7>uhci_hcd 0000:00:1d.0: port 1 portsc 008a,00

[    1.819884] EXT3-fs: sda6: couldn't mount because of unsupported optional features (240).

[    1.862354] kjournald2 starting: pid 748, dev sda6:8, commit interval 5 seconds

[    1.862515] EXT4-fs: mounted filesystem sda6 with ordered data mode

[    6.327269] EXT4 FS on sda6, internal journal on sda6:8
```

My /dev/sda6 partition is the root partition and it has a EXT-4 file system. My /etc/fstab looks like this:

```

/dev/sda6      /               ext4      noatime                        0 1

/dev/sda8      none            swap      sw                              0 0

/dev/cdrom      /media/cdrom   auto      noauto,ro                     0 0

/dev/sda7      /home            ext4      defaults                        0 2

/dev/sda5      /media/datos   ext4      defaults                        0 2

/dev/sda1      /media/windows   ntfs-3g   defaults,locale=es_ES.UTF-8   0 0
```

And I have the same problem in two computers. Anyone would explain me what exactly means these kernel messages ?

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## mikegpitt

I get those errors when mounting my ext4 partitions also, but I never thought they were serious.  I figured that it might try mounting as ext3 before it tries ext4.

----------

