2003-02-18T16:34:53 Jordan Share:
I had the impression that Maildir was the only reasonably safe format over NFS, since there is no locking needed, etc.
Close; I think it's fairer to say that Maildir is the only utterly safe, perfectly bulletproof[1] format over NFS, since no locking is needed. Many people do mbox over NFS, and while NFS locking doesn't work perfectly portably with all combinations of server and client, it _does_ work reliably with specific known-good versions of lockd/statd on a well-supported client against the best-supported NFS server implementations, in whose ranks toasters certainly live.
With care, mbox can be reasonably safe over NFS. I still like Maildir much better.
-Bennett
[1] "Maildir classic", using only hostname, pid, time-to-the-second, and a seqno for single programs performing multiple deliveries, isn't perfectly safe (a) with OpenBSD, which randomizes pids rather than using them sequentially, or (b) with systems capable of very fast forking, in the face of a fork bomb. On most systems today pid-wrapping isn't yet an operational issue in practice, and as maildir implementors are including the inum in the maildir must-be-unique filename, that problem is being solved.