Following up to my own post:
I'm trying to set up Postfix with dovecot LTMP delivery on a host where the user files (/var/spool/mail as well as home directories) are on NFS filesystems, which are exported root-squashed to the mail server.
[LMTP delivery fails with "save failed to INBOX: Read-only mbox"]
I found this posting where someone else had a similar problem and traced it in some detail back in 2019:
https://dovecot.org/list/dovecot/2019-February/114611.html
but apparently no one answered the fellow.
However, he was definitely on the right track, that is, file access was (incorrectly) checked as root, using "access()", instead of as the target user, using "euidaccess()".
I patched "src/lib-storage/index/mbox/mbox-storage.c" and "src/lib-storage/index/maildir/maildir-storage.c" to replace calls to "access()" with calls to "euidaccess()", and now mail delivery (to mboxes) works for me. (I can't test maildir yet.)
Could this be considered for a patch to future versions, please?
Anne.
Ms. Anne Bennett, Senior Sysadmin, ENCS, Concordia University, Montreal H3G 1M8 anne@encs.concordia.ca +1 514 848-2424 x2285