SERVER-2988 catch exceptions loading chunksize

Conflicts:

	s/config.cpp

1 files changed, 38 insertions, 27 deletions

diff --git a/s/config.cpp b/s/config.cpp
index 645e9236a43..9017eafbddd 100644
--- a/s/config.cpp
+++ b/s/config.cpp
@@ -710,42 +710,53 @@ namespace mongo {
         set<string> got;
 
         ScopedDbConnection conn( _primary, 30.0 );
-        auto_ptr<DBClientCursor> c = conn->query( ShardNS::settings , BSONObj() );
-        assert( c.get() );
-        while ( c->more() ) {
-            BSONObj o = c->next();
-            string name = o["_id"].valuestrsafe();
-            got.insert( name );
-            if ( name == "chunksize" ) {
-                LOG(1) << "MaxChunkSize: " << o["value"] << endl;
-                Chunk::MaxChunkSize = o["value"].numberInt() * 1024 * 1024;
-            }
-            else if ( name == "balancer" ) {
-                // ones we ignore here
-            }
-            else {
-                log() << "warning: unknown setting [" << name << "]" << endl;
-            }
-        }
 
-        if ( ! got.count( "chunksize" ) ) {
-            conn->insert( ShardNS::settings , BSON( "_id" << "chunksize"  <<
-                                                    "value" << (Chunk::MaxChunkSize / ( 1024 * 1024 ) ) ) );
-        }
+        try {
 
+            auto_ptr<DBClientCursor> c = conn->query( ShardNS::settings , BSONObj() );
+            assert( c.get() );
+            while ( c->more() ) {
+
+                BSONObj o = c->next();
+                string name = o["_id"].valuestrsafe();
+                got.insert( name );
+                if ( name == "chunksize" ) {
+                    int csize = o["value"].numberInt();
+
+                    // validate chunksize before proceeding
+                    if ( csize == 0 ) {
+                        // setting was not modified; mark as such
+                        got.erase(name);
+                        log() << "warning: invalid chunksize (" << csize << ") ignored" << endl;
+                    } else {
+                        LOG(1) << "MaxChunkSize: " << csize << endl;
+                        Chunk::MaxChunkSize = csize * 1024 * 1024;
+                    }
+                }
+                else if ( name == "balancer" ) {
+                    // ones we ignore here
+                }
+                else {
+                    log() << "warning: unknown setting [" << name << "]" << endl;
+                }
+            }
 
-        // indexes
-        try {
+            if ( ! got.count( "chunksize" ) ) {
+                conn->insert( ShardNS::settings , BSON( "_id" << "chunksize"  <<
+                                                        "value" << (Chunk::MaxChunkSize / ( 1024 * 1024 ) ) ) );
+            }
+
+            // indexes
             conn->ensureIndex( ShardNS::chunk , BSON( "ns" << 1 << "min" << 1 ) , true );
             conn->ensureIndex( ShardNS::chunk , BSON( "ns" << 1 << "shard" << 1 << "min" << 1 ) , true );
             conn->ensureIndex( ShardNS::chunk , BSON( "ns" << 1 << "lastmod" << 1 ) , true );
             conn->ensureIndex( ShardNS::shard , BSON( "host" << 1 ) , true );
+                
+            conn.done();
         }
-        catch ( std::exception& e ) {
-            log( LL_WARNING ) << "couldn't create indexes on config db: " << e.what() << endl;
+        catch ( DBException& e ) {
+            warning() << "couldn't load settings or create indexes on config db: " << e.what() << endl;
         }
-
-        conn.done();
     }
 
     string ConfigServer::getHost( string name , bool withPort ) {