[Dovecot] mbox on NFS + automount, folder creation -> mkdir_parents() failed

[Sebastian Kayser]

Hi,

i am about to migrate some internal imapd mboxes to dovecot. Regular
access is fine, just when i want to create a folder i get the following
error message in the logs:

Mar 18 17:36:57 pulsar dovecot: [ID 107833 mail.error] IMAP(skayser):
mkdir_parents(/home/skayser) failed: Operation not applicable

/home/skayser is mounted via autofs. When i set mail_location to a
subdirectory within /home/skayser, folder creation works. From looking
at the truss output dovecot tries to mkdir() the parent and doesn't
seem to like the ENOSYS that is returned when the directoy is an autofs
mountpoint.

Any chance for a fix, Timo? :)

1549:   poll(0x00117818, 3, 1800000)    (sleeping...)
1549:   poll(0x00117818, 3, 1800000)                    = 1
1549:   read(0, " a 0 0 0 8   S T A T U S".., 3832)     = 38
1549:   stat64("/home/skayser/foobar3", 0xFFBFF598)     Err#2 ENOENT
1549:   write(1, " a 0 0 0 8   N O   M a i".., 41)      = 41
1549:   poll(0x00117818, 3, 1800000)                    = 1
1549:   read(0, " a 0 0 0 9   U I D   C O".., 3794)     = 31
1549:   stat64("/home/skayser/foobar3", 0xFFBFF600)     Err#2 ENOENT
1549:   write(1, " a 0 0 0 9   N O   [ T R".., 53)      = 53
1549:   poll(0x00117818, 3, 1800000)    (sleeping...)
1549:   poll(0x00117818, 3, 1800000)                    = 1
1549:   read(0, " a 0 0 1 0   C R E A T E".., 3763)     = 24
1549:   stat64("/home/skayser/foobar3", 0xFFBFF620)     Err#2 ENOENT
1549:   stat64("/home/skayser/foobar3", 0xFFBFF688)     Err#2 ENOENT
1549:   mkdir("/home/skayser", 0770)                    Err#89 ENOSYS
1549:   write(2, "01 E m k d i r _ p a r e".., 64)      = 64
1549:   write(1, " a 0 0 1 0   N O   I n t".., 99)      = 99
1549:   poll(0x00117818, 3, 1799999)    (sleeping...)

# mount | grep skayser
/home/skayser on nfs:/export/home/skayser remote/read/write/setuid/xattr/dev=490000a

# dovecot -n
# 1.1.11: /opt/csw/etc/dovecot.conf
# OS: SunOS 5.9 sun4u  
disable_plaintext_auth: no
login_dir: /var/opt/csw/run/dovecot/login
login_executable: /opt/csw/libexec/dovecot/imap-login
mail_location: mbox:~/:INBOX=/mail/%u
mmap_disable: yes
mail_nfs_storage: yes
mail_nfs_index: yes
mail_drop_priv_before_exec: yes
mail_executable: /usr/local/bin/dovecot-imap-wrapper.sh
auth default:
  passdb:
    driver: pam
  userdb:
    driver: passwd

Sebastian