# When to use DEVICE=8391

**URL:** <https://techcommunity.softwareag.com/t/when-to-use-device-8391/197273>\
**Category:** Forum\
**Tags:** Adabas-Natural, Adabas, Adabas-on-Mainframes, Adabas-Basics-on-Mainframes\
**Created:** [November 29, 2017, 2:33pm UTC](https://techcommunity.softwareag.com/t/when-to-use-device-8391/197273 "2017-11-29T14:33:01Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Sandy\_Spencer](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/sandy_spencer/32/1219_2.png) [@Sandy\_Spencer](https://techcommunity.softwareag.com/u/Sandy_Spencer)\
**Post date:** [November 29, 2017, 2:33pm UTC](https://techcommunity.softwareag.com/t/when-to-use-device-8391/197273/1 "2017-11-29T14:33:01Z")

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I see that we have defined ASSO, DATA, WORK, SORT, CLOG and PLOG with DEVICE=8391. The documentation (Device and File Considerations) states that DEVICE=8390, 8391, 8392, and 8393 is suitable for 3390 device types, and specifies the block size and RABNs per track associated with each device. We are currently using 3390 mod 9 devices and have just been asked to clone this system using 3390 mod 27 disk packs. Should we continue to define these with DEVICE=8391?

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**Author:** ![system](https://global.discourse-cdn.com/techcommunity/original/3X/c/d/cd19967bb605d28a72d77eb83a1cae22f3df2eb8.svg) [@system](https://techcommunity.softwareag.com/u/system)\
**Post date:** [April 2, 2021, 3:39pm UTC](https://techcommunity.softwareag.com/t/when-to-use-device-8391/197273/2 "2021-04-02T15:39:43Z")

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