NewValidation: Config rollback issue "failed to apply tree: Target source or destination ep/epg not under same tenant as policy"

[rg5147]

(use upvote 👍 for attentions)

Validation Type

[ ] - Fault

[x ] - Config

[ ] - Bug

[ ] - Other

What needs to be validated

This validation is to alert customer of unsupported config.
This will NOT cause upgrade to fail, however rollback of the config wil fail which can be a problem during maintenance window
issue documented here
https://techzone.cisco.com/t5/Application-Centric/ACi-Config-rollback-issue-quot-failed-to-apply-tree-Target/ta-p/17535066

For a config validation, describe the exact configuration to be validated

How to identify if there is a config issue

1. Get the list of DNs
   a-apic1# moquery -c dbgacEpToEp | grep ^dn

2. For each dn get the child objects and check the dbgac.RsToEpIpForEpToEp and dbgac.RsFromEpIp
   a-apic1# moquery -d "uni/tn-rgatti-garmin-tenant1/acEpToEp-rgatti-ep-ep" -x rsp-subtree=children

3. See if the tenant is the same for both dbgac.RsToEpIpForEpToEp and dbgac.RsFromEpIp. If not then print a warning below -
   Use of atomic counters is not supported when the endpoints are in different tenants or in different contexts (VRFs) within the same tenant.
   The atomic policy config is documented in the config guide
   https://www.cisco.com/c/en/us/td/docs/dcn/aci/apic/5x/basic-configuration/cisco-apic-basic-configuration-guide-53x/management-53x.html#Cisco_Concept.dita_e240b341-cd4f-4d0c-88a6-586c22140bfa

Please delete the unsupported config and then proceed with the upgrade.

Why it needs to be validated

Config rollback will fail

Additional context

None