In 8i and 9i archiver process doesn’t automatically startup when database is archive log mode so using the SQL below one can verify if archiver is running on database that has archive log mode turned on.

SQL> SELECT
DECODE(d.log_mode, 'ARCHIVELOG',
DECODE(i.archiver, 'STOPPED',
'Issue archiver not running on archivelog database',
'NoIssue archiver running on archivelog database'),
'NoIssue No archive log mode') archiver_status
from v$database d, V$instance i

Sample Output:
When the archiver is not running on a database that has archive log mode turned on, the above SQL would display the following message

ARCHIVER_STATUS
————————————————-
Issue archiver not running on archivelog database

Information on archivelog mode
How to change archivelog/noarchivelog