mon: disallow adding a tier on top of another tier

multiple tiering is not supported at the moment

Fixes: #11840
Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/mon/OSDMonitor.cc b/src/mon/OSDMonitor.cc
index 22ab5c6120e4b3c107e47fecf75140d85df00ee8..84545bff402033d3277f81ca5e99e54b4f15de36 100644 (file)
--- a/src/mon/OSDMonitor.cc
+++ b/src/mon/OSDMonitor.cc
@@ -7357,6 +7357,14 @@ bool OSDMonitor::_check_become_tier(
     return false;
   }
 
+  if (base_pool->is_tier()) {
+    *ss << "pool '" << base_pool_name << "' is already a tier of '"
+      << osdmap.get_pool_name(base_pool->tier_of) << "', "
+      << "multiple tiers are not yet supported.";
+    *err = -EINVAL;
+    return false;
+  }
+
   if (tier_pool->is_tier()) {
     *ss << "tier pool '" << tier_pool_name << "' is already a tier of '"
        << osdmap.get_pool_name(tier_pool->tier_of) << "'";