SHADOW MAX UNIT

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SHADOW_MAX_UNIT is a system parameter that specifies the maximum number of shadow sets that can exist on a system. The setting must be equal to or greater than the number of shadow sets you plan to have on a system. Dismounted shadow sets, unused shadow sets, and shadow sets with no write bitmaps allocated to them are included in the total. NOTE Review this default carefully. The setting must be equal to or greater than the number of shadow sets you plan to have on a system. If you attempt to mount more shadow sets than the number specified by SHADOW_MAX_UNIT, the MOUNT command will fail. Dismounted shadow sets, unused shadow sets, and shadow sets with no write bitmaps allocated to them are included in the count for SHADOW_MAX_UNIT. On Alpha and Integrity servers, the default value for this system parameter is 500, which consumes 24 KB of main memory. If you do not plan to use Volume Shadowing for OpenVMS, you can change the setting to its minimum of 10 (which consumes 480 bytes of main memory). Setting the default to its minimum frees up 23.5 KB of main memory on an OpenVMS Alpha or Integrity servers and 4.5 KB of main memory on a VAX system. (The maximum value of this parameter is 10,000.) This system parameter is not dynamic; that is, a reboot is required when you change the setting.