Re: ORA-12541, but listener IS running

On 15 Jul 2004 11:27:14 -0700, fred_at_computrition.com (fred) wrote:

>Just built a new linux box, installed a 10g database. I CAN connect to
>it using sqlplus when run on that very box.
>
>But from any other client machine I get the dreaded 12541, no
>listener, error.
>
>But the listener is running. netstat -a shows port 1521 listening. the
>listener shows in "ps ax | grep oracle". "lsnrctl status" says it is
>running.
>
>The linux firewall IS DISABLED. "/etc/rc.d/init.d/ipfilter status"
>shows that it is not running.
>
>running nmap against that machine from another linux box does NOT show
>port 1521 being open. running it against another oracle server does
>show it open.
>
>So, someone, somewhere, is blocking access to 1521 on the new box, but
>I can't figure out who/what/where. Suggestions please?

host = in listener.ora must match host= in tnsnames.ora, otherwise you'll get 12541.

--
Sybrand Bakker, Senior Oracle DBA