server=dedicated

[RamHardikar]

hi,

i have oracle instance running on a server configured as MTS. on a client machine, the tnsnames.ora holds the entry for a particular DB. in the 'connect_data' section there is an entry called 'server=dedicated'. if i try to connect to the database thru my client it does connect. but if remove this entry in the tnsnames.ora the client fails to connect to the server and gives the following message - 'ora-12545: connect failed because the target host or object does not exist'.

so my question is when the oracle instance is configured for MTS why do i have to specify 'server=dedicated' in tnsnames.ora ?

 

[sem]

Dedicated connections are used for sessions that need intensive data exchange (data loading).

server=dedicated directive should be removed with enclosing brackets. It may also be placed to sqlnet.ora file as use_dedicated_server = ON. In this case it will affect all connections.

 

[rcurva]

You user SERVER=DEDICATED in tnsnames.ora to make dedicated connections in a MTS setup. My best guest is, even though you have setup MTS in your site, connections are still dedicated.

Can you check it from v$session?
Robbie

"The rule is, not to besiege walled cities if it can possibly be avoided" -- Art of War

 

[RamHardikar]

sem:

the intensive data operation is at a later stage not while trying to connect to the DB from the client machine using SQL Plus.

and yes, the directive 'use_dedicated_server = ON' in the sqlnet.ora file affects all connection.

 

[sem]

You can not change "connection style" within session, so if you plan to make a lot of work, you shouldn't connect using MTS to avoid "pinging" between server processes and sharing resources with other users. Dedicated connections are normally used by privileged users while shared - by ordinary. Connect time doesn't depend on this parameter a lot, because a number of dedicated processes may be launched during startup.

 

[RamHardikar]

rcurva :

you are right. using the directive 'server=dedicated' i can make a dedicated connection to the MTS oracle server. but my question is - cant i make a connection to the server without using 'server=dedicated' directive when the instance is configured as MTS ?

and yes, in the table v$session i can see if the connection is dedicated.

 

[sem]

If your server is MTS, you may use either of types.
But your error was probably caused by syntax error in tnsnames.ora file. Did you remove brackets around that clause?

 

[rcurva]

Yes, without the SERVER=DEDICATED directive you should still connect via MTS setup. But if you are encountering problems like ORA-12545, most likely, you have a problem with hostname resolution.
Robbie

"The rule is, not to besiege walled cities if it can possibly be avoided" -- Art of War

 

[RamHardikar]

sem:

like i said if i just specify the directive it works. so i dont think its a problem with the tnsnames.ora.

i do not understand why u asked me to remove brackets around the clause. even with brackets it works. no probs with that.

 

[RamHardikar]

rcurva:

i have already made entries in the HOST file on the client machine. but still it fails to connect.

 

[sem]

I suggested to remove both brackets and SERVER=DEDICATED or none. If you remove statement and leave brackets, the structure of file will be corrupted and the name misspelled. I've got the same error if leaving empty pair of brackets within CONNECT DATA clause.

 

[RamHardikar]

sem:

i hv tried that but it fails. now i feel that the rule of thumb is to have that clause in the tnsnames.ora or sqlnet.ora to connect from client.

 

[sem]

In general the rule of thumb is to do not have that clause at all and use it for massive data loads and some administrative tasks only.
I'm still sure that your error was due to the wrong syntax. Try to recreate complete entry, there may be some invisible characters or smth else.

 

[RamHardikar]

sem:

i hv deleted the tnsnames.ora files and hv re-created it using 'net8 easy' but still the same error. i doubt if i hv to set few other things in some other files ?

 

[RamHardikar]

hi,

instead of specifying nothing i have also tried using 'server=shared' but no luck. the funnest part is even other colleagues are not able to connect to the server unless they specify 'server=dedicated' clause. so i doubt there must be some other setting for this to work.

 

[rcurva]

I suppose you may need to check your MTS configuration again because there are several items involved with the ORA-12545 error. Mostly in tnsnames.ora and the mts initialization parameters.

Robbie

"The rule is, not to besiege walled cities if it can possibly be avoided" -- Art of War