note number of DBIs required

diff --git a/modules/lmdbbackend/lmdbbackend.cc b/modules/lmdbbackend/lmdbbackend.cc
index 768fb2c65b5c3a80bfefb7e8c47e13231e2192c6..84b91c00bbcf43d170932f501f9fc190f5f63fb7 100644 (file)
--- a/modules/lmdbbackend/lmdbbackend.cc
+++ b/modules/lmdbbackend/lmdbbackend.cc
@@ -79,7 +79,7 @@ std::pair<uint32_t, uint32_t> LMDBBackend::getSchemaVersionAndShards(std::string
     throw std::runtime_error("mdb_env_set_mapsize failed");
   }
 
-  if ((rc = mdb_env_set_maxdbs(env, 20)) != 0) {
+  if ((rc = mdb_env_set_maxdbs(env, 20)) != 0) {   // we need 17: 1 {"pdns"} + 4 {"domains", "keydata", "tsig", "metadata"} * 2 {v4, v5} * 2 {main, index in _0}
     mdb_env_close(env);
     throw std::runtime_error("mdb_env_set_maxdbs failed");
   }