topic Re: Broker VM connection issue in Cortex XDR Discussions

Broker VM connection issue

Rocky-25 — Thu, 24 Aug 2023 14:25:05 GMT

Hi Community

We're facing an connection issue with Endpoints using Broker VMs (agent proxy). We opened a TAC case, but it's stuck. There is no useful help yet.

- Endpoints are isolated from the internet (no direct or webproxy access)
- Endpoints are registered in Cortex, but doesn't get content updates
- Live terminal to endpoints is not possible
- Brokers connect to the internet through a webproxy
- Webproxy has whitelisted the URLs* (no Authentication, no TLS Interception)

We've checked the following:
- Re-installed agents
- Re-deployed brokers
- Connection from endpoints to brokers is successful (tcp8888)
- Connection from brokers to URLs* is successful (https)

Has anyone some useful information or connectivity tests we can run?

*) https://docs-cortex.paloaltonetworks.com/r/Cortex-XDR/Cortex-XDR-Pro-Administrator-Guide/Resources-Required-to-Enable-Access

Thanks & Best regards

Re: Broker VM connection issue

aspatil — Fri, 25 Aug 2023 11:44:35 GMT

Hello Roman,

We have not came across such scenarios. This case requires TAC intervention.

If it is stuck, I would suggest reaching out to Accounts Team to accelerate the progress.

Thanks!

Re: Broker VM connection issue

Rocky-25 — Fri, 25 Aug 2023 14:42:59 GMT

Hi Community

Finally we figured out what caused this issue!

The brokers transmits all HTTP packets to the webproxy with the endpoints IP addresses as source.
So the webproxy blocked the connections as we only add the brokers IP addresses on the URL whitelist.

We mainly focused on connections between the brokers and webproxy/internet. However, because webproxy rules apply on application layer, we overlooked this.

After activating content caching on the brokers (and tcp443 connections) everything works fine.

Best regards