You don't mention whether or not you'll have more than one HP-UX system accessing the mail spool. If it's just one, then no problem, stop reading here. If more than one system can access the same mailbox (i.e. load balancing), read on.
There are two mailbox formats commonly used. One is 'mbox' the other is 'maildir'. 'mbox' format mailboxes are the most common. They use one file for multiple messages. File locking is always an issue with this format. 'maildir' format is one file per message. This format is generally headache-free in terms of file locking.
My experience is that relying on lockd for file locking works 99.9...% of the time. Your milage can and will vary here.
Not all NFS clients are made the same. Some UNIX vendors have better NFS and NLM (Network Lock Manager) clients than others. While I don't have direct experience with HP-UX, in small environments, lockd should work fine. (Although in a past life, I've run a F630 cluster with at least 8 Solaris based clients and 250,000 mailboxes relying on lockd with no problems.)
If you run into problems, then you should convert to the maildir format. This will require that you patch or change your local delivery agent (the program that sendmail calls to actually write the email to a file, probably mail.local) and your qpopper.
Aaron
-----Original Message----- From: Todd Watson [mailto:tkw@southwestern.edu] Sent: Tuesday, August 07, 2001 3:34 PM To: toasters@mathworks.com Subject: qpopper file locks
My apologies if this question has been hashed over before on the list, but the archives seem inaccessible at the moment.
We are planning on migrating our mail spool files from an HP-UX server to our 740 filer and then mounting them back via NFS. This HP system runs sendmail and pop (qpopper specifically). We are concerned about file-locking issues which may arise or any other "gotchas" that we should be aware of.
Thanks!
Todd
Todd K. Watson Senior System & Network Administrator Southwestern University, Georgetown, TX tkw@southwestern.edu || TEL:512.863.1508 || FAX:512.863.1605