I'm having trouble getting my reverse DNS ACLs working on my server. I set the reverse DNS about 10 hours ago, but it still has not propagated. The problem is that the TTL on reverse DNS is 24 hours. So, I have to wait another 14 hours till I can get my server running. I think this should be set to a more reasonable 1 hour. Also, the TTL should be noted on the reverse DNS page of Linode Manager.

The problem is, there are certain key RBLs that will blacklist you if you have a reverse DNS zone positive TTL of less than 12 hours, causing loss of email. (This only applied to reverse zones.)

I don't recall which major RBL it was that was doing this.

Maybe a compromise would be to make the default reverse DNS have a lower TTL. People running a mail server would set a reverse hostname, right?

I don't have to mention how much I despise admins who use RBLs without reading about them first.

Or how about a compromise of setting the reverse DNS before remote sites have a chance to hit the "default" host name? Or just waiting the (reasonable) default of 24 hours?

It's just a bit inconvenient. I have to setup forward DNS, wait my TTL, then setup reverse DNS, wait Linode's update cycle, then I can boot up my server with the IP. There's a bit of waiting in there.

Waiting 24 hours before I can start setting up a new server is not reasonable. Maybe 20 years ago it was. These days, when I click to create a new server, I expect it now, not tomorrow.

I think the problem is right about here:



Why not use IP addresses? They don't change very often, and it'll save a number of DNS queries on each connection. Few things, other than e-mail and IRC, truly care about reverse DNS.

I guess it's hard to administer based on IP address. If I want see a list of servers that have access to my mysqld, I only get a list of IPs, which mean nothing to me.