NFS errors on directories with many files

[dberger]

I'm hosting IMAP mailboxes on a ReadyNAS Pro 4 (running firmware 4.2.26). The mailboxes are mounted over NFS on a Linux (Ubuntu 12.04) server running dovecot - one of the users complained that they suddenly stopped being able to access their mailbox.

The following appears in the IMAP server log:

Oct 5 16:27:14 vigilance dovecot: imap(nise): Error: readdir(/pensive/Home/nise/Maildir/cur) failed: Too many levels of symbolic links
Oct 5 16:27:14 vigilance kernel: [249959.213572] NFS: directory Maildir/cur contains a readdir loop.Please contact your server vendor. The file: 1394491503.M757191P5231Q0R34a969c8dce7a857.vigilance:2,l^C has duplicate cookie 30107461

the internet tells me this is a known problem created by widening the readdir cookie (apparently their mailbox grew to contain enough messages that it's overflowing the 32 bit cookie) - http://lwn.net/Articles/544520/ - and that the only solution involves a kernel upgrade to the NFS server.

Can someone from Linksys comment on the possibility of this being fixed in a future firmware release?

[Skywalker]

I can't speak for Linksys ;-), but we should be able to address that in a beta release soon.

[dberger]

Do I feel silly - I was fighting multiple issues at the same time and got my vendors crossed.

Sorry.

And that's great 🙂