lxc-checkconfig: Show namespace limits

Closes #4259

Signed-off-by: Stéphane Graber <stgraber@stgraber.org>

diff --git a/src/lxc/cmd/lxc-checkconfig.in b/src/lxc/cmd/lxc-checkconfig.in
index 361d4d98c7b840dc99d36f7ac42be1d86caf8882..c77da4d3d3727c850ff46789fea4b7fe2f2674ed 100755 (executable)
--- a/src/lxc/cmd/lxc-checkconfig.in
+++ b/src/lxc/cmd/lxc-checkconfig.in
@@ -160,6 +160,14 @@ if [ $KVER_MAJOR -lt 4 ] || { [ $KVER_MAJOR -eq 4 ] && [ $KVER_MINOR -lt 7 ]; };
     printf "Multiple /dev/pts instances: " && is_enabled DEVPTS_MULTIPLE_INSTANCES
     echo
 fi
+echo "Namespace limits:"
+for file in /proc/sys/user/max_*_namespaces; do
+    [ -r "${file}" ] || continue
+
+    ns_name="$(basename "${file}" | sed -e "s/^max_//g" -e "s/_namespaces$//g")"
+    printf "  %s: %s" "${ns_name}" "$(cat "${file}")"
+    echo
+done
 
 echo "
 --- Control groups ---"