qmail

Chapter 18. A Compendium of Tips and Tricks

The good thing about qmail is that there are simple ways to perform a wide variety of mail handling tasks, even though qmail doesn’t have as many task-specific features as other MTAs. The bad thing is that the simple ways are often a less than obvious combination of more basic qmail features. Here is a list some common problems, and some of those tasks and combinations.

Qmail Won’t Compile

You have unpacked the qmail sources and typed make, but it won’t compile. If you’re receiving error messages about errno, you’ve run into a compatibility problem between qmail and recent versions of the GNU C library. The fix is very simple. See Building with Recent GLIBC and Fixing the errno Problem in Chapter 3.

(This is the number one question on the qmail mailing list, so frequent that there’s an autoresponder that mails back the answer to any message that contains the word “errno”.)

Why Qmail Is Delivering Mail Very Slowly

If qmail seems to wait about half a minute to do anything when you inject mail, the problem is almost certainly that the lock/trigger file used to communicate between qmail-queue and qmail-send is messed up. That file should be a named pipe:

# ls -l /var/qmail/queue/lock/trigger
prw--w--w-  1 qmails  qmail  0 Nov  7 03:02 /var/qmail/queue/lock/trigger

If it’s a regular file or anything other than a pipe, you have a problem. Fortunately, it’s a problem that’s easy to fix:

# svc -td /service/qmail-send # shut qmail down for a minute # tail ...