how can i execute a ping command

[wilfredo doming]

hi experts,
can you help me on my problem,im trying to execute several command in a ssh server remotely,i'm stuck with some linux command because it gave me no output,im trying to ping a server(xxxx),server name is from the input of a user, and trying to run a command that would stop and start the database remotely...
sample command(/etc/init.d/postgresql restart;ping xxxx)
any help would be greatly appeciated,,
im stuck here for 2 days...thanks

[Mario Minutolo]

Originally posted by wilfredo doming:
hi experts,
can you help me on my problem,im trying to execute several command in a ssh server remotely,i'm stuck with some linux command because it gave me no output,im trying to ping a server(xxxx),server name is from the input of a user, and trying to run a command that would stop and start the database remotely...
sample command(/etc/init.d/postgresql restart;ping xxxx)
any help would be greatly appeciated,,
im stuck here for 2 days...thanks

You cannot PING in Java, as far as I know, and I doubt you really need ping in Java.

Check this library Commons NET for common operations like checking a server is online .

Check this one Trilead SSH for Java for SSH operations.

[Henry Wong]

I believe a form of ping has been added to Java 5. Take a look at the isReachable() method of the InetAddress class. At minimum, this method should use the ping port to determine reachability.

Henry

[wilfredo doming]

thanks for the reply,actually im already using trilead SSH in my project,i cannot use this command(sess.exec("ping l.getHostName()")),im looking for alternative solutions..and any idea on how the stop/start thing in SSH can be executed using sess.exec()??

[Pat Farrell]

look up the System.exec() call, it can execute any generic shell command.

Whether that will be useful is a separate topic. Try it from a shell.
You may find that the server doesn't respond to the ping command, that firewalls block it, etc.

But if you can get a shell to do

ping somehost.foo.bas

then you can use System.exec() to do it.

[Joanne Neal]

I think Pat meant to say Runtime.exec().
And if you're using Java 1.5 or later you could also use ProcessBuilder.

[wilfredo doming]

thanks,another problem is when i execute a certain command,it prompts me to enter the same password again,maybe for verification.this regards with the stop/start thing.i manage to execute it,but the output is not what ive expected...when the command is executed it goes straight to the next password,but it cannot get the value of my set password,then the program reads that i enter a blank password,which i want is to get the value of the password i set...
here is the output
STDERR password:
Password: su: incorrect password
STDERR:..failed
STDOUT:Starting PostgreSQL

i want to get the same password to be able to execute the command..

thanks,your help is much appreciated

[ August 27, 2008: Message edited by: wilfredo doming ]
[ August 27, 2008: Message edited by: wilfredo doming ]