Disable TLSv1 and TLSv1.1 on port 443 in Managed cluster

[CharlesWu]

Dynatrace managed is enabled on TLSv1 and v1.1 on the user communication port 443. We are required to disable both. How can we do that? I tested the port 8443 for OneAgent communication, and only TLSv1.2 is enabled.

[CharlesWu]

In /opt/dynatrace-managed/server/conf/config.properties file, the line "ssl-protocols=TLSv1.2" is set, but TLSv1 and TSLv1.1 are not disabled. Do we have similar option to disable them as we did in AppMon dtfrontendserver.ini and dtserver.ini by passing "-Dcom.dynatrace.diagnostics.ssl.protocols.unsafe=TLSv1,TLSv1.1" ?

[Julius_Loman · Accepted solution]

In case of Dynatrace Managed, the 443/tcp port (in recent versions, I think it is from v136) is handled by bundled NGINX. Settings in server's config.properties are not applied for nginx.

Actually, it's just a matter of adding:

ssl_protocols TLSv1.2;

To the config file /opt/dynatrace-managed/nginx/conf/nginx.conf and restart the nginx. Add the line after the existing ssl settings.

If you have a multinode cluster, you will have to do that on every node.

[parthasaradhi_a]

Which section we need to add this parameter in config.properties ?

[Julius_Loman]

It's not in config.properties, but in nginx.conf.

[CharlesWu]

It works. The test from openssl returns "Secure Renegotiation IS NOT supported" on TLSv1 and 1.1. Nice. Thanks so much Julius!

[CharlesWu]

It comes to another problem that auto-update keeps overwriting nginx configuration, so TLSv1.0 and v1.1 Vulnerability keeps coming back. Every time I have to manually fix it. Can Dynatrace Vendor permanently fix this issue in the new updates/releases?

[Julius_Loman]

Did you open a support ticket for that? This forum answer can get unnoticed.

[tarun_agastya2]

Hi Charles,

Did you get any fix from dynatrace support.We are also having same issue every time new updates/releases happening we are loosing TLSv1.2 Vulnerabilities and TLSv1.0 & 1.1 coming back.

Can you please let us know if you receive any fix.

Appreciate your help.

Tarun

[CharlesWu]

No. Not sure if our Dynatrace sales engineer submitted a case for this, and I had to update the config file right after every update. Now I just submitted a "RFE - Please remediate SSL Vulnerability on Dynatrace managed to have TLSv1.2 enabled only" in the Dynatrace product ideas. Please go there to vote, so we can get it fixed soon. Thanks for the reminder.

[miroslaw_swiatk · Accepted solution]

You can find an answer to this question in our documentation:

https://www.dynatrace.com/support/help/setup-and-configuration/dynatrace-managed/installation/custom...

in the section "SSL certificates parameters"