issues using in a firewall rule

Showing results for 
Show  only  | Search instead for 
Did you mean: 

issues using in a firewall rule

L4 Transporter

Microsoft makes extensive use of the name to map to thousands of IPs in its Akamai content delivery network.

I find that i have issues trying to use FQDN host object in a firewall rule. Many times traffic doesnt hit the rule.

I suspect its because Palo's periodic update of its IP table for misses some of the addresses in use.

Has anyone else experienced this?  I'm running PA 9.1.13


Community Team Member

Hi @JimMcGrady ,


What do you have set for your minimum FQDN refresh time? You can try setting it to 0. refresh The FQDN refresh will be based on the TTL set in DNS. 

LIVEcommunity team member
Stay Secure,
Don't forget to Like items if a post is helpful to you!

Please help out other users and “Accept as Solution” if a post helps solve your problem !

Read more about how and why to accept solutions.

Cyber Elite
Cyber Elite


The issue that you'll run into, even if setup as @JayGolf mentioned, is that CDNs like Akami don't have the TTL set to expire as often as they rotate clients to different hosts. This is slightly better if you have the firewall and all connected clients using the same DNS servers, but you can still have the firewall and the client get out of sync even then.

With Microsoft in particular I highly recommend using URL Filtering to limit this traffic instead of trying to utilize FQDN objects if you can. There's imperfect lists of associated Windows update IPs that you can tie with URL Filtering in more secure environments, but FQDNs never work properly for this. 

  • 2 replies
  • 101 Subscriptions
Like what you see?

Show your appreciation!

Click Like if a post is helpful to you or if you just want to show your support.

Click Accept as Solution to acknowledge that the answer to your question has been provided.

The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!

These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the LIVEcommunity as a whole!

The LIVEcommunity thanks you for your participation!