ORACLE error while dbstart command I'm trying to start up Oracle DB with startup command. 
But error occurred while startup.

dbstart[80]: test: argument expected
Failed to auto-start Oracle Net Listene using /bin/tnslsnr
touch: $ORACLE_HOME/startup.log cannot create
chmod: $ORACLE_HOME/startup.log: No such file or directory
Processing Database instance "$ORACLE_SID": log file $ORACLE_HOME/startup.log
No such file or directory
dbstart[350]: $ORACLE_HOME/startup.log: cannot create


How can I fix it?  Oracle Database 10g Release 10.2.0.1.0 - 64bit Production is running under AIX.
I have faced the similar issue. The reason, why it has happened was the invalid entry in the /etc/oratab.

As dbstart script suggests, to configure, update /etc/oratab with instances that need to be started up. The entries are of the form:

$ORACLE_SID:$ORACLE_HOME:&lt;N|Y|W&gt;:


An example entry:

main:/usr/lib/oracle/emagent_10g:Y