Hey everyone! I'm managing two DHCP servers and I'm curious about how to set up DHCP and DNS scavenging properly. Here are the specifics:
- **DHCP Server 01:** Has several scopes: 200 leases set to 8 days, 1 infinite lease, and others at various intervals (1 to 4 days).
- **DHCP Server 02:** Has 40 leases set to 8 days.
Both servers are set up for DHCP Failover Hot-standby, and dynamic updates for DNS are enabled when requested by clients.
I have a few questions:
1. What happens to other dynamic DNS records such as _msdsc, _services, _sites, etc.? Are they deleted during scavenging?
2. Since I have various lease periods, what should my DNS scavenging refresh and non-refresh times be?
3. With multiple DNS servers across different locations, should I configure only one for scavenging? Which one would be best? Should it have the FSMO role?
4. For the case where I have a parent and a child domain (e.g., contoso.domain and company.com), if scavenging is enabled only on the child domain and not the parent, will the parent zone's stale records also be affected when I enable scavenging on the child?
Overall, is my current setup for DNS aging and scavenging sufficient for the contoso.domain configuration?
1 Answer
Hey! I faced similar worries before diving into this. If scavenging is set up correctly, records that are actively in use should be updated and won't be scavenged. What I did was run a PowerShell script to back up every zone daily, so I had a 30-day history just in case of accidental deletions. I also turned on scavenging on just one server to keep the logs centralized.
As for lease times, it’s often best to use Microsoft’s default for standard setups and maintain custom times for special cases like public wireless areas. Just take your time with the configuration and it will work out!
Check out more about DNS scavenging [here](https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/dns-scavenging-setup).
Can you explain the concepts of NoRefresh, Refresh, and Scavenging in more detail? Also, if you have a script to share, that would be awesome!