I've run into a bit of a snag and could really use some help. We recently changed our DHCP subnet to a /22 in order to provide new IP addresses for our machines, but now I'm facing an issue where devices with these new IPs can't join our Active Directory. Interestingly, if I revert them back to some of the previous IPs, they have no trouble joining. We also have an IPsec tunnel to an AWS instance to access the AD.
What's puzzling is that the machines with the new IPs can ping both the domain and the DNS server without a problem, but joining the domain is a whole different story. Does anyone have any suggestions on how to resolve this issue?
1 Answer
First off, make sure you've updated the subnet mask on all your devices, including the servers. I once took over a school network that had changed from a /24 to a /22 but missed the web filter update, which ended up causing all sorts of connectivity issues. When you change subnets, you need to update everything - DHCP, routing rules, servers, and all the services they provide. Otherwise, you could end up with partial connectivity like you’re seeing.
Yeah, updating everywhere is key! Sometimes those little details get overlooked and can cause big headaches!