Is there any documentation for creating a database link between 11g and 10g database

0. you are working at 11g database

1. tnsnames.ora has an entry like this for 10g database at your 11g database server

ora10g =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = db10gserver)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = db10g)
    )
  )

-->> tnsping ora10g                  at command prompt, is the result successful ?

2. db link command is correct, following is the syntax

CREATE [PUBLIC] DATABASE LINK dblink
[CONNECT TO user IDENTIFIED BY password]
[USING connect_string]

for example:

create public database link db10g
connect to db10gUserName identified by password
using ora10g;

--->> test this dblink              select * from tblName@db10g;

sonicefu,

where are you getting these suggestions from?
I agree with everything you've said, but only if the error is in resolving the names between the 10g and 11g databases or for 2, if  the error is in syntax of creating the link.

but, the asker hasn't told us that.  Is there a related question you're pulling extra info from?  or are you just guessing?  if the former,  which?  if the latter, that's fine,  I'm just curious.

@sdstuber

How are you boss ?

following are the answers of your questions
 
Is there a related question you're pulling extra info from?   10%

or

are you just guessing?  90%   -->>> mostly these are the things which create problems in db links, i think you'll agree with me.

There is an error message. My client has said he will provide it when he calls me at 11 AM.

Here is what he did and the error he is getting:

create database link TEMSDB.LOCAL
  connect to TEMSLOAD identified by ********
  using '(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=000.000.00.128)(PORT=1521))
                      (CONNECT_DATA=(SERVICE_NAME=url)))';

 

We also have a synonym defined for the BIB_HOLDINGS_COMPARE table&

 

create or replace synonym TEMSDATATABLE
  for TEMSLOAD.BIB_HOLDINGS_COMPARE@TEMSDB.LOCAL;



When I connect to our database as the owner of the two objects above, and try this query&

 

select count(1)
from temsdatatable

 

I get the following error:

 

ORA-12170: TNS:Connect timeout occurred

Just to add they also changed operating systems. They were running 9.2.0.4 on Sun V880/Solaris. Now they are running 11g on Windows 2003 server

also, what are your sqlnet.ora settings for timeouts?

He tried this is the result:
tnsping (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=000.000.00.128)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=url)))    

The first took a very long time so I aborted.  

The second reported timeouts on all 4 packet requests.

ping ip address

this is the problem

from what he said it appears that he can login but when he tries to query he gets the timeout error

They were running 9.2.0.4 on Sun V880/Solaris.  i think ip address of this server was 192.168.58.128

Now they are running 11g on Windows 2003 server --> ask them for the ip address of this server and replace it in the following

create database link TEMSDB.LOCAL
  connect to TEMSLOAD identified by ********
  using '(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=000.000.00.128)(PORT=1521))
                      (CONNECT_DATA=(SERVICE_NAME=url)))';

--> actually this is the network problem

yep!

000.000.00.128 is 10g server they are trying to connect from 11g to 10g

ok,  but if you can't reach that server (ping failures tell you that), then you can't create a db link to it either.

or, more accurately,  you can create the link  (as you've already seen)

you just can't use it (as you've already seen)


either that's not really the ip address or you've got a horrible network lag between your 11g server and your 10g server.

based on the ip address itself (000.*.*.*)  , that's probably going across a vpn or some other small sub-network.   Is the vpn down ?

Thank you for the document.

Hi all,

Thank you all so much for your input it was extremely valuable and instrumental in helping me solve my clients problem. The issue was network related. Although I don't have the details they were able to resolve the issue with not being able to ping the 10g database server and then connect successfully and query via the database link. Thank You all!

Not only was my question answered (Can someone tell me what kind of questions I can ask to help them troubleshoot this issue and any relevant Oracle documentation?) but a solution was provided. My client contacted the network administrators and they identified and fixed the problem. Thank you all!

I found one more modus_operandi: ID 21814129 Thanks!