11G R2: Oracle Cluster SCAN Listeners: Use easy connect naming method

Posted in: Technical Track

Just recently I came across another unclear error message while troubleshooting an Oracle Instance registration with SCAN Listener. This post is one of the posts which may save quite a bit of time for people who will hit the same issue.

The errors message I got configuring a database just moved to run under 11GR2 Oracle Cluster control is as following:

SQL> alter system set remote_listener='scan.usolygrid-prod.cinram.com:1521';
alter system set remote_listener='scan.your.domain.com:1521'
ERROR at line 1:
ORA-02097: parameter cannot be modified because specified value is invalid
ORA-00119: invalid specification for system parameter REMOTE_LISTENER
ORA-00132: syntax error or unresolved network name

I was quite sure that the syntax I used was 100% correct as other instances running on the same host used the same remote_listener parameter value.

It appears that someone adjusted the following string in sqlnet.ora file on the server:


The change makes sense to me as it always good to have strict control on where tns names are sourced from on the servers side.

However it appears that Oracle use an easy connect naming method to register Oracle Instances in SCAN Listeners by default. Therefore EZCONNECT keyword should be present in sqlnet.ora file. Strictly speaking you can use other tns names as the resolution method for the remote_listener parameter but by default it uses the easy connect naming method and you may face the error message shown above if you omit the EZCONNECT keyword.

I hope this post may save you some troubleshooting time.


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About the Author

Yury is a nice person who enjoys meeting and working with people on challenging projects in the Oracle space. He started to work as an Oracle DBA 14 years ago (1997). For the past 10 years (since 2001) his main area of expertise is Oracle e-Business Suite. Yury is an OCP 7,8,9,10g and OCM 9i,10g. He is a frequent presenter at Oracle related conferences such as Hotsos, UKOUG and AUOUG. Yury is a socially active person. Apart from Social Media (Twitter, Bloging, Facebook) he is the primary organizer of Sydney Oracle Meetup group (250 people). So if you happen to be in Sydney (Australia) drop Yury a message and stop by at one of his Meetups.

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Thanks for this SCAN tip. Saved me hours of poking around


Awesome, you saved my evening!! Kudos!!


Glad to know that it helped you. Thanks for letting me know :)


I just resolved this issue , opened the wizard using netca and configured the local naming method option and seleted local connect & Easy connect and finished the setup internally it will configure these two connnection. and restarted the database , now it is working fine .

I did change manually added the EZCONNECT name in sqlnet.ora file, it’s not workedout.



Thanks for the article.

I resolved a problem on one of our production dbs with this

God Bless


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