DBU uses QTEMP to prevent issues with users in the same file and can not be in the system or product library list. The way to avoid having DBU in the user portion of the library list is to follow the steps below.
1. CRTDUPOBJ OBJ(DBU) FROMLIB(DBU10) OBJTYPE(*CMD) TOLIB(QGPL)
2. CHGCMD CMD(DBU) CURLIB(DBU10)
When you upgrade to DBU11, you will have to delete the command in QGPL and do steps 1 and 2 again for DBU11.
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