If you write system procedures and store them in sybsystemprocs, you can recover them, when necessary, either by restoring the database, or by loading database backups. .
Restore the database from installmaster. Then re-create the procedures by reissuing the create procedure commands.
Keep backups of the database, and load them with load database.
If you choose to keep a backup of the database, be sure that the complete backup fits on one tape volume or that more than one SAP ASE is can communicate with your Backup Server. If a dump spans more than one tape volume, issue the change-of-volume command using sp_volchanged, which is stored in sybsystemprocs. You cannot issue that command in the middle of recovering a database.
load database sybsystemprocs from "/dev/nrmt4"
load database sybsystemprocs from "\\.\TAPE0"