access mySql via multiple ssh in java -


i'm new ssh , have question. have connect via ssh gateway , within ssh session i've ssh server. can connect mysql server.

  1. ssh <gateway>
  2. ssh -l3306:db02:3306 username@db02

then can configure putty , heidysql access mysql database. far, good.

but want access mysql database via java code. googled , found code use jsch.

so, below result of code. when run code, session okay, portforwarding okay.

but part giving me error:

connection con = drivermanager.getconnection("jdbc:mysql://localhost:"+nlocalport, strdbuser, strdbpassword);

this error: java.sql.sqlexception: access denied user 'dbuser'@'gateway.appl.local' (using password: yes)

it seems port forwarding not done because of error shows connect gateway: 'dbuser'@'gateway.appl.local'

after succesfull port forwarding should show this: dbuser'@'**db02**.appl.local

import com.jcraft.jsch.jsch; import com.jcraft.jsch.jschexception; import com.jcraft.jsch.session;  import java.sql.connection; import java.sql.drivermanager; import java.sql.sqlexception; import java.util.properties;  public class mysqlconnoverssh {     private static void dosshtunnel( string strsshuser, string strsshpassword, string strsshhost, int nsshport, string strremotehost, int nlocalport, int nremoteport ) throws jschexception     {         final jsch jsch = new jsch();         session session = jsch.getsession( strsshuser, strsshhost, 22 );         session.setpassword( strsshpassword );          final properties config = new properties();         config.put( "stricthostkeychecking", "no" );         session.setconfig( config );         session.connect();         session.setportforwardingl(nlocalport, strremotehost, nremoteport);     }      /**      * java program connect remote database through ssh using port forwarding      * @throws sqlexception      */     public static void main(string[] args) throws sqlexception {         try         {             string strsshuser = "sshusername";                           // ssh loging username             string strsshpassword = "sshpassword";               // ssh login password             string strsshhost = "10.20.0.234";          // hostname or ip or ssh server             int nsshport = 22;                                    // remote ssh host port number             string strremotehost = "db02";  // hostname or ip of database server             int nlocalport = 3307;                                // local port number use bind ssh tunnel             int nremoteport = 3306;                               // remote port number of database             string strdbuser = "dbuser";                    // database loging username             string strdbpassword = "dbuserpw";                    // database login password              mysqlconnoverssh.dosshtunnel(strsshuser, strsshpassword, strsshhost, nsshport, strremotehost, nlocalport, nremoteport);              class.forname("com.mysql.jdbc.driver");             connection con = drivermanager.getconnection("jdbc:mysql://localhost:"+nlocalport, strdbuser, strdbpassword);             con.close();         }         catch( exception e )         {             e.printstacktrace();         }                 {             system.exit(0);         }     } }

this quite slow, if absolutely have to, set tunnel across both connections:

on local host: ssh -l3306:localhost:3306 user@host1 on host1:           ssh -l3306:localhost:3306 user@db02

then should able connect 3306 on local system , tunneled through 3306 on db02. if host1 running mysql , don't want interfere it, use different intermediate port, in

on local host: ssh -l3306:localhost:3316 user@host1 on host1:           ssh -l3316:localhost:3306 user@db02

Comments

Post a Comment

Popular posts from this blog

jOOQ update returning clause with Oracle -

according http://www.jooq.org/doc/3.8/manual/sql-building/sql-statements/update-statement/ jooq doesn't support returning clause in update statements databases except firebird , postgres. does know, still correct oracle jooq? according oracle's documentation, oracle db supports returning clase delete, insert, or update statements. incorrect manual you're right - manual wrong , should fixed: https://github.com/jooq/jooq/issues/5470 single row update returning jooq 3.8 added support single row update .. returning statements. internally, uses callablestatement , pl/sql block of form: begin update "my_table" set "my_table"."column" = 'xyz' "my_table"."id" = 1 returning "my_table"."id", "my_table"."column" ?, ?; ? := sql%rowcount; end; the relevant issue is: https://github.com/jooq/jooq/issues/5190 multi row update returning a...
Read more

java - Warning equals/hashCode on @Data annotation lombok with inheritance -

i have entity inherits other. on other hand, i'm using lombok project reduce boilerplate code, put @data annotation. annotation @data inheritance produces next warning: generating equals/hashcode implementation without call superclass, though class not extend java.lang.object. if intentional, add '@equalsandhashcode(callsuper=false)' type. is advisable add annotation @equalsandhashcode (callsuper = true) or @equalsandhashcode (callsuper = false) ? if not added, 1 callsuper=false or callsuper=true ? the default value false . 1 if don't specify , ignore warning. yes, recommended add @equalsandhashcode annotation on @data annotated classes extend else object. cannot tell if need true or false , depends on class hierarchy, , need examined on case-by-case basis. however, project or package, can configure in lombok.config call super methods if not direct subclass of object. lombok.equalsandhashcode.callsuper = call for configuration system ...
Read more

java - BasicPathUsageException: Cannot join to attribute of basic type -

i using java 8 jpa (hibernate 5.2.1). have clause works perfectly, until introduce clause make use foreign key table values too. i getting following error: basicpathusageexception: cannot join attribute of basic type i think problem related fact have join table, , not sure how create join using join table. employee - employee_category - category model (employee.java): @manytomany(cascade = cascadetype.all, fetch=fetchtype.eager) @jointable ( name="employee_category", joincolumns={ @joincolumn(name="emp_id", referencedcolumnname="id") }, inversejoincolumns={ @joincolumn(name="cat_id", referencedcolumnname="id") } ) private set<category> categories; model (category.java): @id private string id; jpa when introduce following code, fails error above (i think problem new piece of code): join<t, category> category = from.join("id"); predicates.add(criteriabuilder.like(category....
Read more