add systemd note

diff --git a/docker.sysconfig b/docker.sysconfig
index 8ac1cf7d1aa9761166c290c016e678799979472e..4f3191ce1144131a92c6dcf23505616f4429cbc5 100644 (file)
--- a/docker.sysconfig
+++ b/docker.sysconfig
@@ -7,6 +7,10 @@ SERVICE_RUN_NICE_LEVEL="+0"
 SERVICE_LIMITS="-n 1048576 -u 1048576"
 
 # Modify these options if you want to change the way the docker daemon runs
+# IMPORTANT:
+# When using systemd, do not use variables in variables:
+#  OPTIONS="$OPTIONS --foo"
+# ... systemd parser does not handle these
 #OPTIONS=""
 
 # Use overlay storage driver