Hi, As documented here ( https://mariadb.com/kb/en/mariadb/mariadb-galera-cluster-known-limitations/) :
> > - A command may fail with ER_UNKNOWN_COM_ERROR producing 'WSREP has > not yet prepared node for application use' (or 'Unknown command' in older > versions) error message. It happens when a cluster is suspected to be split > and the node is in a smaller part — for example, during a network > glitch, when nodes temporarily lose each other. It can also occur during > state transfer. The node takes this measure to prevent data inconsistency. > Its usually a temporary state which can be detected by checking > wsrep_ready > <https://mariadb.com/kb/en/galera-cluster-status-variables/#wsrep_ready> > value. > The node, however, allows SHOW and SET command during this period. > > if you have only 2 nodes : Quorum requires a majority, meaning that you cannot have automatic failover in a two node cluster. This is because the failure of one causes the remaining node automatically go into a non-primary state. Diego. On Wed, Nov 23, 2016 at 12:00 AM, l vic <lvic4...@gmail.com> wrote: > i have the following jdbc exception in my jdbc client for the node 1 after > another node (node2) is removed: > om.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: > WSREP has not yet prepared node for application use > at sun.reflect.GeneratedConstructorAccessor9.newInstance(Unknown > Source) > at sun.reflect.DelegatingConstructorAccessorImpl.newInstance( > DelegatingConstructorAccessorImpl.java:45) > at java.lang.reflect.Constructor.newInstance(Constructor.java:423) > at com.mysql.jdbc.Util.handleNewInstance(Util.java:404) > at com.mysql.jdbc.Util.getInstance(Util.java:387) > at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:917) > at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3966) > at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3902) > at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2526) > at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2673) > at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545) > at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2503) > at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1369) > at com.mysql.jdbc.ConnectionImpl.loadServerVariables( > ConnectionImpl.java:3833) > at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer( > ConnectionImpl.java:3283) > at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly( > ConnectionImpl.java:2297) > at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083) > at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806) > at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) > at sun.reflect.GeneratedConstructorAccessor5.newInstance(Unknown > Source) > at sun.reflect.DelegatingConstructorAccessorImpl.newInstance( > DelegatingConstructorAccessorImpl.java:45) > at java.lang.reflect.Constructor.newInstance(Constructor.java:423) > at com.mysql.jdbc.Util.handleNewInstance(Util.java:404) > at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410) > at com.mysql.jdbc.NonRegisteringDriver.connect( > NonRegisteringDriver.java:328) > at java.sql.DriverManager.getConnection(DriverManager.java:664) > > I wonder why i have this failure when i just trying to read db from the > unaffected node? The failure seems to be permanent, once it happened - all > subsequent reads fail > > _______________________________________________ > Mailing list: https://launchpad.net/~maria-discuss > Post to : maria-discuss@lists.launchpad.net > Unsubscribe : https://launchpad.net/~maria-discuss > More help : https://help.launchpad.net/ListHelp > >
_______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp
