How to check if a VIP supports http/2

Question

Hi Team ,&nbsp;How to check if the VIP supports http version 2 ?&nbsp;client is getting below error for http v 2.0&nbsp;&nbsp;

michael_saleem · Answer

You can check by issuing a cURL command to the virtual server (this can be done directly from the BIG-IP's bash shell)
run util bash

curl -IvLk --http2 https://&lt;FQDN&gt;
If you see the following in the result output, then this means that the virtual server is not configured to support HTTP/2. You will need to create an http2 profile and a compatible client SSL profile (httprouter profile and server SSL profile will be needed too if you want HTTP/2 Full proxy) and apply it to the virtual server.
&nbsp;

ALPN, server did not agree to a protocol

aswin_mk · Answer

Hello,&nbsp;You can test this curl command aswell - curl -I --http2 -k https://&lt;VIP&gt;

f5_design_engineer · Answer

Hi Blue_Whale,
&nbsp;
To check if a Virtual IP (VIP) on your F5 LTM supports HTTP/2, you can follow these steps:
1. Check the HTTP/2 Profile Assignment
Ensure that the virtual server has an HTTP/2 profile assigned to it. You can do this via the F5 Configuration utility or the command line.
Using the Configuration Utility:

Log in to the F5 Configuration utility.
Navigate to: Local Traffic -&gt; Virtual Servers.
Select the virtual server you want to check.
Go to the "Resources" tab and look for the "HTTP/2 Profile" under "HTTP Profiles".

Using the Command Line:
You can use the tmsh command to list the virtual server configuration and check for the HTTP/2 profile.
tmsh list ltm virtual &lt;virtual_server_name&gt; profiles
Look for an HTTP/2 profile in the output.
2. Verify HTTP/2 Support with Command Line Tools
You can use command line tools like curl to verify if the VIP supports HTTP/2.
curl -I --http2 https://&lt;VIP_IP&gt;

-I: Fetches the headers only.
--http2: Forces the use of HTTP/2.

If the VIP supports HTTP/2, you should see HTTP/2 in the response headers.
3. Check the BIG-IP Configuration
Ensure that the BIG-IP system is configured to support HTTP/2. This includes having the necessary profiles and settings in place.
Example Command:
tmsh list ltm profile http2
This command lists all HTTP/2 profiles configured on the system. Ensure that the profile is correctly configured and associated with the virtual server.
4. Review the Documentation
Refer to the F5 documentation for detailed steps on managing HTTP/2 traffic and configuring the HTTP/2 profile.
If you follow these steps and still encounter issues, it might be helpful to check the logs for any errors or warnings related to HTTP/2 traffic.
&nbsp;
Kindly rate
HTH
F5 Design Engineer
&nbsp;

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