Please help: Can't browse NFS share on AC86U using Kodi

[Jiri]

Hi All,
I had a similar nfs problem and solved it by reformatting the USB flash drive to ext4.
My wrt is RT-AC86U running Asus Merlin version 384.15. USB flash disk is SanDisk Ultra fit 128GB, ID 0781:5583.
The error message found in Systemlogs on the server was:

May  5 06:10:02 mountd[1465]: authenticated mount request from 192.168.xxx.xxx:897 for /tmp/mnt/sda1/MyFolder (/tmp/mnt/sda1/MyFolder)
May  5 06:10:02 mountd[1465]: Cannot export /tmp/mnt/sda1/MyFolder, possibly unsupported filesystem or fsid= required

The USB flash disk was formatted as tfat (not a typo, see wiki), and was happily working under under Samba. Formatting that to ext4 made it working under nfs as well. Just setting fsid= to zero or a small integer did not help.

Note there is some documentation on reformatting disk on Asus Merlin here: https://github.com/RMerl/asuswrt-merlin.ng/wiki/Disk-formatting
My recommendations is:
1) back up all your data as reformatting will wipe them all out
2) stop all the services using the USB (Media server, Samba, nfs,..) under General / USB applications / Servers Centre
3) unmount through GUI under General / Network Map / click relevant USB ( 2.0 | 3.0 ) / Sefalle Remove Disk - on the right
4) reformatting under extX is not listed in gui so I went directly for:

mke2fs -t ext4 -O ^has_journal /dev/sda1

I did not bother re-partitioning the disk as suggested in the above manual. That's an overkill for this purpose.
5) Don't forget starting all the services again.

Note I also remapped uid and gid of my Samba user to match the one present on the nfs network by using
/jffs/scripts/passwd.postconf and /jffs/scripts/group.postconf .

I hope that helps anyone else affected.

Good luck.

 

[ColinTaylor]

The USB flash disk was formatted as tfat (not a typo, see wiki), and was happily working under under Samba. Formatting that to ext4 made it working under nfs as well. Just setting fsid= to zero or a small integer did not help.

How did you determine it was formatted as TFAT? If you were looking at the output of the mount command "tfat" is just the name of Tuxera's FAT driver.

 

[john9527]

I think you need to specify the nfsvers....here's the mount command I use for testing
mount -t nfs -o defaults,nfsvers=3 192.168.1.1:/mnt/ASUS /mnt/asus

 

[Salles]

Hi All,
I had a similar nfs problem and solved it by reformatting the USB flash drive to ext4.
My wrt is RT-AC86U running Asus Merlin version 384.15. USB flash disk is SanDisk Ultra fit 128GB, ID 0781:5583.
The error message found in Systemlogs on the server was:

May  5 06:10:02 mountd[1465]: authenticated mount request from 192.168.xxx.xxx:897 for /tmp/mnt/sda1/MyFolder (/tmp/mnt/sda1/MyFolder)
May  5 06:10:02 mountd[1465]: Cannot export /tmp/mnt/sda1/MyFolder, possibly unsupported filesystem or fsid= required

The USB flash disk was formatted as tfat (not a typo, see wiki), and was happily working under under Samba. Formatting that to ext4 made it working under nfs as well. Just setting fsid= to zero or a small integer did not help.

Note there is some documentation on reformatting disk on Asus Merlin here: https://github.com/RMerl/asuswrt-merlin.ng/wiki/Disk-formatting
My recommendations is:
1) back up all your data as reformatting will wipe them all out
2) stop all the services using the USB (Media server, Samba, nfs,..) under General / USB applications / Servers Centre
3) unmount through GUI under General / Network Map / click relevant USB ( 2.0 | 3.0 ) / Sefalle Remove Disk - on the right
4) reformatting under extX is not listed in gui so I went directly for:

mke2fs -t ext4 -O ^has_journal /dev/sda1

I did not bother re-partitioning the disk as suggested in the above manual. That's an overkill for this purpose.
5) Don't forget starting all the services again.

Note I also remapped uid and gid of my Samba user to match the one present on the nfs network by using
/jffs/scripts/passwd.postconf and /jffs/scripts/group.postconf .

I hope that helps anyone else affected.

Good luck.

Thank you for your answer. Appologies for a late reply.

My 4TB HD is formatted to Ext4 with journaling according to the described guide. Since nothing else is wrong, I do not think that is the issue.

I have not looked into uid and guid of Samba and NFS. I am not really sure what you mean. Is this done in the WebUI?
My Samba share is allowed with guest login and and workgroup WORKGROUP.
Rergarding NFS Export I see no user or group id.

 

[Jiri]

How did you determine it was formatted as TFAT? If you were looking at the output of the mount command "tfat" is just the name of Tuxera's FAT driver.

Most likely by analysis output of

cat /etc/mtab

, entered on ssh command line. That's definitely the first think I would look at.

 

[Jiri]

... .I have not looked into uid and guid of Samba and NFS. I am not really sure what you mean. ...

This is specific to my application, but will generally apply to any solution that mixes samba and nfs. On any linux box, each user has a user id (uid) and group id (gid).

These are typically assigned when a user is created. Ubuntu or the Raspberry Pi start numbering from 1000.
Asus Merlin aparently starts from 500.

In my application, user 'pi' has uid 1000 on a Raspberry Pi, but it was assigned 501 when created as a Samba user on Asus Merlin.

nfs respects uid and gid of the client, Samba enforces its own, server - Asus Merlin - defined.
Thus a pi user cannot access his own file is created via Samba (uses uid 501) if he subsequently access it using nfs (that respects clients uid of 1000).

I used /jffs/scripts/passwd.postconf and /jffs/scripts/group.postconf scripts to alter uid and gid in stored in /etc / p a s s w d and /etc / g r o u p from 501 to 1000.

I hope this makes sense this way.

 

[ColinTaylor]

Most likely by analysis output of

cat /etc/mtab

, entered on ssh command line. That's definitely the first think I would look at.

In which case it was using FAT not TFAT as tfat is the name of the FAT driver.

 

[Jiri]

In which case it was using FAT not TFAT as tfat is the name of the FAT driver.

Very interesting thanks. I am glad to learn something new.
I was expecting some improved version of FAT. I remember I heard somewhere there was, in contemporary terms, a relatively small max volume limit limit for FAT. The stick was a 128GB one.

 

[ColinTaylor]

Very interesting thanks. I am glad to learn something new.
I was expecting some improved version of FAT. I remember I heard somewhere there was, in contemporary terms, a relatively small max volume limit limit for FAT. The stick was a 128GB one.

FAT32 has a maximum volume size of 2TB (or 16TB using 4k sectors). More problematic nowadays is the maximum file size of <4GB.

 

[K-2SO]

I was expecting some improved version of FAT.

There is - https://en.wikipedia.org/wiki/ExFAT
It allows >4GB files. I use it for my USB sticks. Not compatible with my car audio.

 

[ColinTaylor]

There is - https://en.wikipedia.org/wiki/ExFAT
It allows >4GB files. I use it for my USB sticks. Not compatible with my car audio.

But not supported by the router. Up until late last year it was a proprietary format which would need to be licensed from Microsoft. Linux support was limited.

 

[K-2SO]

But not supported by the router.

I know. Improved FAT though. This is why I ended with . Car audio was compatibility hint.

 

[ColinTaylor]

I know. Improved FAT though. This is why I ended with . Car audio was compatibility hint.

I just wan't to be sure anyone reading your post didn't come away thinking that the router supported exFAT. Unless these things are explicitly stated somebody's going to be posting a "my flash drive isn't mounted" thread.