?????????????IP???????????????????????????????Starting TNS Listener or LSNRCTL Start Yields TNS-12541?? Linux Error: 111: Connection Refused (??? ID 343295.1)???????????????????????????????????????￡????/etc/hosts?????????????????????
[oracle@getlnx01 ~]$ more /etc/hosts
# Do not remove the following line?? or various programs
# that require network functionality will fail.
127.0.0.1      localhost.localdomain localhost
192.168.7.221  getlnx01.esqule.com getlnx01
CAUSE
1. There is possibly an incorrect IP Address specified for the host in the /etc/hosts file.
For example:
192.168.101.101 prod1.us.oracle.com prod1
Whereas the actual ip address for the host "prod1.us.oracle.com" is 192.168.101.110
2. Also?? the localhost reference may be incorrect or missing from the /etc/hosts file.
3. Oracle may not have read access to /etc/nsswitch.conf file.
SOLUTION
To implement the solution?? please execute the following steps:
1. Correct the mapping in the /etc/hosts file by adding/correcting the IP address and/or hostname reference for the Unix/Linux Server (both long and short host names).
For example:
# Add or edit the /etc/hosts file to include a valid entry for the Server:
192.168.101.110 prod1.us.oracle.com prod1
2. Check that the localhost loopback name and address are correct (both long and short host names).
An example of a correct localhost entry would be as follows:
127.0.0.1 localhost.localdomain localhost
3. Remember to save the /etc/hosts file and then start the listener.
4. Check permissions on /etc/nsswitch.conf file to ensure group and other have read access.
- If necessary change permisions on /etc/nsswitch.conf as follows:
chmod 644 /etc/nsswitch.conf