Oren Laadan orenl@cs.columbia.edu writes:

Russ Allbery wrote:

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orenl@cs.columbia.edu writes:

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Our configuration uses both BDB and META back-ends; as it turns out the standard debian package of LDAP fails to run with the META back-end configured (see also complaints here: http://www.openldap.org/lists/openldap-bugs/200705/msg00011.html and here: http://arkiv.netbsd.se/?ml=OpenLDAP-bugs&a=2007-02&t=3076794).

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Yeah, we're still trying to figure out the best way to fix that. libtool has some serious problems with how it handles namespaces when dynamically loading modules, and fixing one set of problems creates a separate set of problems. (This particular problem is Debian-specific and not a problem with the upstream OpenLDAP.)

:(

Well, the good news is that it isn't a show-stopper, and the simple workaround is to compile the code from scratch.

Specifically, the workaround is to compile the code with the upstream libtool instead of with Debian's libtool, since upstream libtool imports all module symbols into the global namespace. Debian's libtool has been modified to not do this because it causes all sorts of other problems in the general case, but not doing this breaks the meta backend because it wants to reference symbols from the bdb backend.

Steve had an ugly hack to work around this by linking the meta backend against the bdb backend. Doing that isn't the ugly part -- that's actually formally correct and really is what libtool should be doing in the first place. The ugly part is that libtool *really* doesn't like linking against something that doesn't start with lib*.

What's really bothering me, is that the system repeatedly and frequently hangs with my configuration ... (my users aren't happy with me recently). Do you have any idea how to investigate that ?

Not beyond the standard advice to investigate what the server is doing during a hang using gdb attach or strace.

We have yet to have a chance to do intensive testing of 2.4.7. (Debian testing really is a testing distribution that doesn't have production stability.)