Questions[msdcs](server)

I just realized that a previous admin turned DNS scavenging on for all zones on one of the DCs, including the _msdcs zone. It's been this way for a while and things are fine, but I can't imagine that this is best practice.

Is there any danger to scavenging the _msdcs zone?
Should I make it so that zone is not scavenged?
Could scavenging have broken anything in that zone that I'm unaware of at this time?

I hope everybody had a good July 4th!

Looking through my DNS entries, I see the following:

My questions are:

1. How do I identify which of these belongs to the current domain?
2. Is it safe to delete the rest of them or should I just leave them all alone? Is there any harm done in keeping them?
3. How are these ids generated?

The reason I'm asking these is because I have had to rebuild Active Directory on a domain controller a few times and have had to use the same name. What I've been left with is a single _ldap record of that domain controller inside the _tcp record for every one of those entries. I suspect that some of these are remnants of that process and I'm trying to cleanup stale records. I've tried scavenging but they persist.

Thank you.

I have _msdcs Active Directory Integrated. Do I need to enable Zone transfers and notifications on changes? I have 2 domain controllers with DNS/DHCP enabled on them? I would think yes, but it's disabled and I am not sure why? Windows 2008 R2 controllers were migrated from Windows 2003.