An export already exists for the host string

[kstripp]

Brief description of the problem

New to Rockstor, so I probably have bungled something somewhere. Additionally, while I have many years of linux experience, I’ve never quite gotten NFS right… so the likely hood of buglement there is quite high.

I created an NFS export, but then realized that I needed no_root_squash. At first I thought I needed to use advanced editing to get this, and it appeared that I could only do that while creating an export. So I deleted the export I had already made, and added one through advanced editing. But that didn’t show up under exports, which didn’t seem right, so I deleted that and went back to the regular creation screen. I then saw that the admin ip option sets no_root_squash, so I tried re-making the share with that… only to get the error in the screenshot.

Any suggestions would be appreciated. Thanks!

Detailed step by step instructions to reproduce the problem

I think these are the steps I took

1. Create an NFS share using the normal screen
2. Delete the share
3. Create (or attempt to) the share via advanced editing
4. Delete the share from the advanced editor
5. Attempt to create the share using the “Add NFS Export” button
6. Get the error message
7. Delete all references to the IP using the system shell, directly editing /etc/exports
8. Attempt to create the share using the “Add NFS Export” button
9. Get the error message

Web-UI screenshot

Error Traceback provided on the Web-UI

NoneType: None (note, the whitespace and newlines was not a mistake; that was in the error message)

[unguul (Alexandru Ungureanu)]

TLDR: remove all exports, confirm via “Advanced edit” and restart the NFS service.

I had a similar issue recently where one of my exports got stuck but only showed up in the “Advanced edit” tab. Removing it via nano /etc/exports didn’t fix it, as the export was automatically restored. In my particular case, the stuck export was some snapshot I had made, so I was able to solve the issue by just removing that snapshot.

[kstripp]

Thanks @unguul! I think my original issue managed to resolve itself somehow, maybe by the old snapshots being removed by schedule.

Amusingly though, while trying to resolve my most recent problem, a google search caused me to stumble on my own post and your answer, which turned out to be the key to helping me resolve it!
So for anyone else stumbling on this, here are a few more breadcrumbs that might help.

I had an issue where an NFS export would not start up after a reboot. There was a low level in the rockstor logs saying the NFS export couldn’t be created to to a failed mkdir command.

Error running a command. cmd = /usr/bin/mkdir -p /export/nextcloud/.daily_202406050230. rc = 1. stdout = [\'\']. stderr = [\'/usr/bin/mkdir: cannot create directory ‘/export/nextcloud/.daily_202406050230’: Operation not permitted\', \'\']\n']).

Turns out NFS does not get along with visible shares, as described here:

Can't access NFS shares that have snapshots

I have just discovered that some of my nfs shares are no longer accessible. The ones affected are those I have a scheduled snapshot task for. I have read the wiki detailing how you can’t rollback a snapshot while exported as a share, but I haven’t tried that and they previously worked. Checking the web-UI scheduled tasks page, recent snapshots have failed with an unspecified “error”. Digging into journalctl, I only see: -- The start-up result is done. Feb 13 01:15:01 [myhostname] CROND[24965]…

Unfortunately, the solution there didn’t work for me, as I could not delete the snapshots, I think because they were being exported via NFS. This post lead me to see where I could find that. A lot of going in seeming circles and using chattr -i /export/share/offending_snapshot followed by rm -r /export/share/offending_snapshot eventually got things cleared out, and I was able to delete snapshots. Then I was eventually able to re-make the NFS share, and things started working again.