Cloud Discovery questions

[pbostian]

OK, Brain trust... here's my quandary...

We are migrating massive numbers of our apps to Azure.  Right now, about 145 subscriptions, and maybe 15000 CIs spread across ALL the US Azure data centers.  would be so much easier if they were all centrally located, but.. not my call. 

I have a cloud discovery schedule set up for the group, as the server guys are literally adding and removing subscriptions on a daily basis, but they are all added under this group, which is just below tenant.  So i SHOULD have access to all them , the instant they are added.  

The initial "Group discovery" run is no problem... takes maybe 25 minutes.  When the second schedule kicks in to discover the VMs, it all goes south.  Powershell timeouts, error messages,  and multiple "failed to initialize PowerConsole" errors.  End up fully discovering and updating maybe 25% of the VM CI's in the cloud before it times out after  8 hours.

Is this simply due to the fact that I'm trying to discovery the entire cloud off one mid?  do i need to split up the mids, one per datacenter?  I know i need at least one more mid in azure, following the 10,000 CI to one mid guideline i saw somewhere.  im guessing we might have maybe 1500-2000 VMs max, but i dont know as i cant finish a full discovery run.

Man, cloud discovery is so much more different than regular horizontal/on-prem disco that i. have been doing for years.

Appreciate any guidance and advice anyone can provide.