im new to this JAMF platform. im able to enroll any ipad that is listed under our DEP. my issue is that there is some ipads were not purchased under DEP and their serial number is not listed under the JAMF / Mobile device managemetn section. the question is how to enroll these devices.
You have essentially 3 options.
1: Manually Enroll them (worst).
2: Enroll them with Apple Configurator 2(better).
3: Add them to DEP, if possible(best).
The first 2 options are explained well in the admin guide, and the third one depends heavily on your particular org. If the devices were purchased from apple, but don't show up in DEP, you should be able to add them to DEP using either the Serial Numbers or Order Numbers. This is done in your DEP/ASM portal under Device Assignments. There are some circumstances where iPads purchased from re-sellers can also be added to DEP, but I don't know the specifics on that so I'd recommend talking to your Apple rep if that applies to you.
If you do go the Configurator 2 route, check out this section on Supervision Identities: http://docs.jamf.com/9.98/casper-suite/administrator-guide/Supervision_Identities.html
You can use the same supervision identity between your Configurator 2 computers and DEP which can make life a bit easier.
+1 for the 3 options by @bburdeaux
Option 3 is actually a process that should be done in cooperation with the (original) reseller of the devices.
You (as DEP admin) should give the reseller access to add devices to your DEP account,
The reseller should be 'DEP approved', which means that they have an order system that is audited by Apple. Most resellers (or their distributors) are nowadays, and they can add devices that they sold to your DEP account.
The bottom line is that you can only add 'older devices' to your DEP account, if all the paperwork (and all parties in-between you and Apple) can 'garantee' that this serial number is originally bought by your company, since with DEP you have supervision (i.e. full control) over these devices. In case of doubt, no DEP !
It is supposed to work for older devices bought by your company, but many things can go wrong, so don't count on it to be successful.
(like the name on the invoice is a sister company, or one of the resellers is in a different country than you, like grey-market-side-import, etc)