Today we launched two new features in our DNS Tools package. These solve hours of banging your head against the wall when you’re in the execution phase of a cloud migration project: Bulk hosts file analysis and bulk PTR querying.

/etc/hosts — evil, incarnate

We’ve all been there: “email is down, but we don’t have control over the DNS for it. Let’s update the hosts file to send mail elsewhere without changing the app!”. Well, those decisions tend to build up overtime. Infact, one client recently detected 36,000+ unique hosts file entries across their server environment while preparing for a cloud migration. 36,000! That’s a lot of management overhead and will prevent your migration project from moving smoothly.

![dns-tools hosts -d ](/assets/img/1__LF8ouHeg4HMQsLRRX__MEYg.png) dns-tools hosts -d

Can you PTR me in the right direction?

The opposite of resolving to `` is the PTR record, or “reverse DNS”, which we typically use `dig -x` to resolve to `server-13–33–164–`. When planning a data center or cloud migration, we often change our public IP address space and performing a PTR query against that entire block ahead of time will tell you what you need to know for setting up your new environment. Not having PTR records setup can be harmless, or it can mean no email gets delivered — it is application specific, and often overlooked.

It’s so easy to do our homework with this one-liner, so why not? With, we can now simply:

dns-tools ptr — ip

and save ourselves the headaches of hard-to-troubleshoot outages.

Hint: Yes, US Navy migration project, you can use this too :-)

New Looks

Also today, we have a new look for our website, — let us know what you think of the site, or what other features you’d like to see. Stickers coming soon!

Chief Migration Hacker, Tidal Migrations

PS — Tidal Migrations customers get included with their subscription, for free.