services: nscd: Enable ‘passwd’ and ‘group’ caches by default.

This allows users to specify NSS plugins such as LDAP via the
‘name-services’ field of <nscd-configuration>.  Failing that, user code
will dlopen whatever passwd/group plugins are listed in
/etc/nsswitch.conf, which is likely to fail, typically because those are
not in $LD_LIBRARY_PATH.

* gnu/services/base.scm (%nscd-default-caches): Add ‘passwd’ and ‘group’
caches.

Change-Id: I9c03346a1de2710685f7801eccd2e08007427f5d

1 files changed, 16 insertions, 1 deletions

diff --git a/gnu/services/base.scm b/gnu/services/base.scm
index 984670cd32..5f69b68f79 100644
--- a/gnu/services/base.scm
+++ b/gnu/services/base.scm
@@ -1340,7 +1340,22 @@ the tty to run, among other things."
                     (positive-time-to-live (* 3600 24))
                     (negative-time-to-live 3600)
                     (check-files? #t)             ;check /etc/services changes
-                    (persistent? #t))))
+                    (persistent? #t))
+
+        ;; Enable minimal caching of the user databases, not so much for
+        ;; caching but rather to allow that uses of NSS plugins like LDAP
+        ;; don't lead user processes to dlopen them (which is likely to fail
+        ;; due to them not being found in $LD_LIBRARY_PATH).
+        (nscd-cache (database 'passwd)
+                    (positive-time-to-live 600)
+                    (negative-time-to-live 20)
+                    (check-files? #t)             ;check /etc/passwd changes
+                    (persistent? #f))
+        (nscd-cache (database 'group)
+                    (positive-time-to-live 600)
+                    (negative-time-to-live 20)
+                    (check-files? #t)             ;check /etc/group changes
+                    (persistent? #f))))
 
 (define-deprecated %nscd-default-configuration
   #f