Switching the Server to or from Single-User Mode

New onmode command-line options switch the coserver into single-user mode, or from single-user mode to another mode:

• onmode -j switches the coserver to single-user mode (from on-line mode or from quiescent mode).
• onmode -m switches the coserver to on-line mode from single-user mode.
• onmode -s switches the server to quiescent mode from single-user mode.
• onmode -k switches the server to off-line mode from single-user mode

The onmode -j command is not a graceful shutdown, because it aborts all sessions of users who are not informix, and rolls back their open transactions. Any work being performed by user informix remains intact, however, and the associated client sessions are unaffected by the mode change.

When the server switches to single-user mode, a new alarm is triggered:

SEVERITY   CLASS ID   TAG ID     MESSAGE
2 (Info)   4          9          Database server in Single-User Mode

For more information about command-line options of the onmode utility, see Appendix A. Syntax Summaries of Selected Utilities.