bool Grid::addShard( string* name , const ConnectionString& servers , long long maxSize , string& errMsg ) {
// name can be NULL, so provide a dummy one here to avoid testing it elsewhere
string nameInternal;
if ( ! name ) {
name = &nameInternal;
}
ReplicaSetMonitorPtr rsMonitor;
// Check whether the host (or set) exists and run several sanity checks on this request.
// There are two set of sanity checks: making sure adding this particular shard is consistent
// with the replica set state (if it exists) and making sure this shards databases can be
// brought into the grid without conflict.
if ( servers.type() == ConnectionString::SYNC ) {
errMsg = "can't use sync cluster as a shard for replica set, "
"have to use <setname>/<server1>,<server2>,...";
return false;
}
vector<string> dbNames;
try {
bool ok = false;
{
ScopedDbConnection newShardConn(servers.toString());
BSONObj resIsMongos;
ok = newShardConn->runCommand( "admin", BSON( "isdbgrid" << 1 ), resIsMongos );
newShardConn.done();
}
// should return ok=0, cmd not found if it's a normal mongod
if ( ok ) {
errMsg = "can't add a mongos process as a shard";
return false;
}
if ( servers.type() == ConnectionString::SET ) {
if (!addReplSetShardCheck( servers, &errMsg )) {
return false;
}
// shard name defaults to the name of the replica set
if ( name->empty() && !servers.getSetName().empty() ) {
*name = servers.getSetName();
}
}
// In order to be accepted as a new shard, that mongod must not have any database name
// that exists already in any other shards. If that test passes, the new shard's
// databases are going to be entered as non-sharded db's whose primary is the
// newly added shard.
BSONObj resListDB;
{
ScopedDbConnection newShardConn(servers.toString());
ok = newShardConn->runCommand( "admin", BSON( "listDatabases" << 1 ), resListDB );
newShardConn.done();
}
if ( !ok ) {
errMsg = str::stream() << "failed listing " << servers.toString()
<< "'s databases:" << resListDB;;
return false;
}
BSONObjIterator i( resListDB["databases"].Obj() );
while ( i.more() ) {
BSONObj dbEntry = i.next().Obj();
const string& dbName = dbEntry["name"].String();
if ( _isSpecialLocalDB( dbName ) ) {
// 'local', 'admin', and 'config' are system DBs and should be excluded here
continue;
}
else {
dbNames.push_back( dbName );
}
}
if ( servers.type() == ConnectionString::SET ) {
rsMonitor = ReplicaSetMonitor::get( servers.getSetName() );
}
}
catch ( DBException& e ) {
if ( servers.type() == ConnectionString::SET ) {
ReplicaSetMonitor::remove( servers.getSetName() );
}
errMsg = str::stream() << "couldn't connect to new shard " << causedBy(e);
return false;
}
// check that none of the existing shard candidate's db's exist elsewhere
for ( vector<string>::const_iterator it = dbNames.begin(); it != dbNames.end(); ++it ) {
DBConfigPtr config = getDBConfig( *it , false );
if ( config.get() != NULL ) {
ostringstream ss;
ss << "can't add shard " << servers.toString() << " because a local database '" << *it;
ss << "' exists in another " << config->getPrimary().toString();
errMsg = ss.str();
return false;
}
}
// if a name for a shard wasn't provided, pick one.
if ( name->empty() && ! _getNewShardName( name ) ) {
errMsg = "error generating new shard name";
return false;
}
// build the ConfigDB shard document
BSONObjBuilder b;
b.append(ShardType::name(), *name);
b.append(ShardType::host(),
rsMonitor ? rsMonitor->getServerAddress() : servers.toString());
if (maxSize > 0) {
b.append(ShardType::maxSize(), maxSize);
}
BSONObj shardDoc = b.obj();
{
ScopedDbConnection conn(configServer.getPrimary().getConnString(), 30);
// check whether the set of hosts (or single host) is not an already a known shard
BSONObj old = conn->findOne(ShardType::ConfigNS,
BSON(ShardType::host(servers.toString())));
if ( ! old.isEmpty() ) {
errMsg = "host already used";
conn.done();
return false;
}
log() << "going to add shard: " << shardDoc << endl;
conn->insert(ShardType::ConfigNS , shardDoc);
errMsg = conn->getLastError();
if ( ! errMsg.empty() ) {
log() << "error adding shard: " << shardDoc << " err: " << errMsg << endl;
conn.done();
return false;
}
conn.done();
}
Shard::reloadShardInfo();
// add all databases of the new shard
for ( vector<string>::const_iterator it = dbNames.begin(); it != dbNames.end(); ++it ) {
DBConfigPtr config = getDBConfig( *it , true , *name );
if ( ! config ) {
log() << "adding shard " << servers << " even though could not add database " << *it << endl;
}
}
// Record in changelog
BSONObjBuilder shardDetails;
shardDetails.append("name", *name);
shardDetails.append("host", servers.toString());
configServer.logChange("addShard", "", shardDetails.obj());
return true;
}
bool Grid::addShard( string* name , const ConnectionString& servers , long long maxSize , string& errMsg ) {
// name can be NULL, so provide a dummy one here to avoid testing it elsewhere
string nameInternal;
if ( ! name ) {
name = &nameInternal;
}
ReplicaSetMonitorPtr rsMonitor;
// Check whether the host (or set) exists and run several sanity checks on this request.
// There are two set of sanity checks: making sure adding this particular shard is consistent
// with the replica set state (if it exists) and making sure this shards databases can be
// brought into the grid without conflict.
vector<string> dbNames;
try {
ScopedDbConnection newShardConn(servers.toString());
newShardConn->getLastError();
if ( newShardConn->type() == ConnectionString::SYNC ) {
newShardConn.done();
errMsg = "can't use sync cluster as a shard. for replica set, have to use <setname>/<server1>,<server2>,...";
return false;
}
BSONObj resIsMongos;
bool ok = newShardConn->runCommand( "admin" , BSON( "isdbgrid" << 1 ) , resIsMongos );
// should return ok=0, cmd not found if it's a normal mongod
if ( ok ) {
errMsg = "can't add a mongos process as a shard";
newShardConn.done();
return false;
}
BSONObj resIsMaster;
ok = newShardConn->runCommand( "admin" , BSON( "isMaster" << 1 ) , resIsMaster );
if ( !ok ) {
ostringstream ss;
ss << "failed running isMaster: " << resIsMaster;
errMsg = ss.str();
newShardConn.done();
return false;
}
// if the shard has only one host, make sure it is not part of a replica set
string setName = resIsMaster["setName"].str();
string commandSetName = servers.getSetName();
if ( commandSetName.empty() && ! setName.empty() ) {
ostringstream ss;
ss << "host is part of set " << setName << ", use replica set url format <setname>/<server1>,<server2>,....";
errMsg = ss.str();
newShardConn.done();
return false;
}
if ( !commandSetName.empty() && setName.empty() ) {
ostringstream ss;
ss << "host did not return a set name, is the replica set still initializing? " << resIsMaster;
errMsg = ss.str();
newShardConn.done();
return false;
}
// if the shard is part of replica set, make sure it is the right one
if ( ! commandSetName.empty() && ( commandSetName != setName ) ) {
ostringstream ss;
ss << "host is part of a different set: " << setName;
errMsg = ss.str();
newShardConn.done();
return false;
}
if( setName.empty() ) {
// check this isn't a --configsvr
BSONObj res;
bool ok = newShardConn->runCommand("admin",BSON("replSetGetStatus"<<1),res);
ostringstream ss;
if( !ok && res["info"].type() == String && res["info"].String() == "configsvr" ) {
errMsg = "the specified mongod is a --configsvr and should thus not be a shard server";
newShardConn.done();
return false;
}
}
// if the shard is part of a replica set, make sure all the hosts mentioned in 'servers' are part of
// the set. It is fine if not all members of the set are present in 'servers'.
bool foundAll = true;
string offendingHost;
if ( ! commandSetName.empty() ) {
set<string> hostSet;
BSONObjIterator iter( resIsMaster["hosts"].Obj() );
while ( iter.more() ) {
hostSet.insert( iter.next().String() ); // host:port
}
if ( resIsMaster["passives"].isABSONObj() ) {
BSONObjIterator piter( resIsMaster["passives"].Obj() );
while ( piter.more() ) {
hostSet.insert( piter.next().String() ); // host:port
}
}
if ( resIsMaster["arbiters"].isABSONObj() ) {
BSONObjIterator piter( resIsMaster["arbiters"].Obj() );
while ( piter.more() ) {
hostSet.insert( piter.next().String() ); // host:port
}
}
vector<HostAndPort> hosts = servers.getServers();
for ( size_t i = 0 ; i < hosts.size() ; i++ ) {
if (!hosts[i].hasPort()) {
hosts[i].setPort(ServerGlobalParams::DefaultDBPort);
}
string host = hosts[i].toString(); // host:port
if ( hostSet.find( host ) == hostSet.end() ) {
offendingHost = host;
foundAll = false;
break;
}
}
}
if ( ! foundAll ) {
ostringstream ss;
ss << "in seed list " << servers.toString() << ", host " << offendingHost
<< " does not belong to replica set " << setName;
errMsg = ss.str();
newShardConn.done();
return false;
}
// shard name defaults to the name of the replica set
if ( name->empty() && ! setName.empty() )
*name = setName;
// In order to be accepted as a new shard, that mongod must not have any database name that exists already
// in any other shards. If that test passes, the new shard's databases are going to be entered as
// non-sharded db's whose primary is the newly added shard.
BSONObj resListDB;
ok = newShardConn->runCommand( "admin" , BSON( "listDatabases" << 1 ) , resListDB );
if ( !ok ) {
ostringstream ss;
ss << "failed listing " << servers.toString() << "'s databases:" << resListDB;
errMsg = ss.str();
newShardConn.done();
return false;
}
BSONObjIterator i( resListDB["databases"].Obj() );
while ( i.more() ) {
BSONObj dbEntry = i.next().Obj();
const string& dbName = dbEntry["name"].String();
if ( _isSpecialLocalDB( dbName ) ) {
// 'local', 'admin', and 'config' are system DBs and should be excluded here
continue;
}
else {
dbNames.push_back( dbName );
}
}
if ( newShardConn->type() == ConnectionString::SET )
rsMonitor = ReplicaSetMonitor::get( setName );
newShardConn.done();
}
catch ( DBException& e ) {
if ( servers.type() == ConnectionString::SET ) {
ReplicaSetMonitor::remove( servers.getSetName() );
}
ostringstream ss;
ss << "couldn't connect to new shard ";
ss << e.what();
errMsg = ss.str();
return false;
}
// check that none of the existing shard candidate's db's exist elsewhere
for ( vector<string>::const_iterator it = dbNames.begin(); it != dbNames.end(); ++it ) {
DBConfigPtr config = getDBConfig( *it , false );
if ( config.get() != NULL ) {
ostringstream ss;
ss << "can't add shard " << servers.toString() << " because a local database '" << *it;
ss << "' exists in another " << config->getPrimary().toString();
errMsg = ss.str();
return false;
}
}
// if a name for a shard wasn't provided, pick one.
if ( name->empty() && ! _getNewShardName( name ) ) {
errMsg = "error generating new shard name";
return false;
}
// build the ConfigDB shard document
BSONObjBuilder b;
b.append(ShardType::name(), *name);
b.append(ShardType::host(),
rsMonitor ? rsMonitor->getServerAddress() : servers.toString());
if (maxSize > 0) {
b.append(ShardType::maxSize(), maxSize);
}
BSONObj shardDoc = b.obj();
{
ScopedDbConnection conn(configServer.getPrimary().getConnString(), 30);
// check whether the set of hosts (or single host) is not an already a known shard
BSONObj old = conn->findOne(ShardType::ConfigNS,
BSON(ShardType::host(servers.toString())));
if ( ! old.isEmpty() ) {
errMsg = "host already used";
conn.done();
return false;
}
conn.done();
}
log() << "going to add shard: " << shardDoc << endl;
Status result = clusterInsert( ShardType::ConfigNS,
shardDoc,
WriteConcernOptions::AllConfigs,
NULL );
if ( !result.isOK() ) {
errMsg = result.reason();
log() << "error adding shard: " << shardDoc << " err: " << errMsg << endl;
return false;
}
Shard::reloadShardInfo();
// add all databases of the new shard
for ( vector<string>::const_iterator it = dbNames.begin(); it != dbNames.end(); ++it ) {
DBConfigPtr config = getDBConfig( *it , true , *name );
if ( ! config ) {
log() << "adding shard " << servers << " even though could not add database " << *it << endl;
}
}
// Record in changelog
BSONObjBuilder shardDetails;
shardDetails.append("name", *name);
shardDetails.append("host", servers.toString());
configServer.logChange("addShard", "", shardDetails.obj());
return true;
}
/**
* Performs sanity check on the given connection string on whether the seed list
* is consistent with the view of the set using replSetGetStatus.
*/
bool addReplSetShardCheck( const ConnectionString& servers, string* errMsg ) {
bool ok = false;
BSONObj replSetStat;
try {
ScopedDbConnection newShardConn(servers.toString());
ok = newShardConn->runCommand( "admin", BSON( "replSetGetStatus" << 1 ),
replSetStat );
newShardConn.done();
}
catch ( const DBException& ex ) {
*errMsg = str::stream() << "Error encountered while checking status of "
<< servers.toString() << ": " << causedBy( ex );
}
if( !ok ) {
if ( replSetStat["info"].str() == "configsvr" ) {
*errMsg = "the specified mongod is a --configsvr and "
"should thus not be a shard server";
}
else {
*errMsg = str::stream() << "error encountered calling replSetGetStatus: "
<< replSetStat;
}
return false;
}
// if the shard has only one host, make sure it is not part of a replica set
string setName = replSetStat["set"].str();
string commandSetName = servers.getSetName();
if ( commandSetName.empty() && ! setName.empty() ) {
*errMsg = str::stream() << "host is part of set: " << setName
<< " use replica set url format <setname>/<server1>,<server2>,....";
return false;
}
if ( !commandSetName.empty() && setName.empty() ) {
*errMsg = str::stream() << "host did not return a set name, "
<< "is the replica set still initializing?" << replSetStat;
return false;
}
// if the shard is part of replica set, make sure it is the right one
if ( ! commandSetName.empty() && ( commandSetName != setName ) ) {
*errMsg = str::stream() << "host is part of a different set: " << setName;
return false;
}
// if the shard is part of a replica set, make sure all the hosts mentioned in
// 'servers' are part of the set. It is fine if not all members of the set
// are present in 'servers'.
bool foundAll = true;
string offendingHost;
if ( ! commandSetName.empty() ) {
set<string> hostSet;
BSONElement membersElem( replSetStat["members"] );
if ( membersElem.type() == Array ) {
BSONArrayIteratorSorted iter( BSONArray( membersElem.Obj() ));
while ( iter.more() ) {
hostSet.insert( iter.next()["name"].str() ); // host:port
}
vector<HostAndPort> hosts = servers.getServers();
for ( size_t i = 0 ; i < hosts.size() ; i++ ) {
if (!hosts[i].hasPort()) {
hosts[i].setPort(CmdLine::DefaultDBPort);
}
string host = hosts[i].toString(); // host:port
if ( hostSet.find( host ) == hostSet.end() ) {
offendingHost = host;
foundAll = false;
break;
}
}
}
if ( hostSet.empty() ) {
*errMsg = "replSetGetStatus returned an empty set. "
" Please wait for the set to initialize and try again.";
return false;
}
}
if ( ! foundAll ) {
*errMsg = str::stream() << "in seed list " << servers.toString()
<< ", host " << offendingHost
<< " does not belong to replica set " << setName;
return false;
}
return true;
}