From Oracle FAQ
Svrmgrl is an old utility shipped with Oracle 8i and lower releases (ORACLE_HOME\bin directory). Server manager commands are now available in SQL*Plus. Prior to svrmgrl, DBAs used the SQL*DBA command.
Svrmgrl was used to perform functions like database creation, startup, shutdown, recovery, oradebug, etc.
The INTERNAL user was used to connect to the local instance as defined by the ORACLE_HOME and ORACLE_SID environment variables.
In later releases, the INTERNAL user was replaced with "SYS AS SYSDBA".
Example to shutdown the database:
$ svrmgrl Oracle Server Manager Release 22.214.171.124.0 - Production Copyright (c) 1997, 1999, Oracle Corporation. All Rights Reserved. Oracle8i Enterprise Edition Release 126.96.36.199.1 - Production With the Partitioning option JServer Release 188.8.131.52.1 - Production SVRMGR> connect internal Connected. SVRMGR> shutdown immediate Database closed. Database dismounted. ORACLE instance shut down. SVRMGR> exit Server Manager complete.
Take a systemstate dump:
$ svrmgrl Oracle Server Manager Release 184.108.40.206.0 - Production (c) Copyright 1997, Oracle Corporation. All Rights Reserved. Oracle8 Enterprise Edition Release 220.127.116.11.1 - Production With the Partitioning option PL/SQL Release 18.104.22.168.1 - Production SVRMGR> connect internal Connected. SVRMGR> oradebug setmypid Statement processed. SVRMGR> oradebug unlimit Statement processed. SVRMGR> oradebug dump systemstate 1 Statement processed. SVRMGR> exit; Server Manager complete.
Also see, Enterprise Manager for GUI and Web-based management interfaces.