Fortiweb : SSE (servent sent event) [Accept: text/event-stream] KO when HTTP2 enabled

[ajdonik]

Hi,

I am running an SPA (JS) application behind fortiweb in monitor mode.

When HTTP2 is activated, the https (http2) request keeps infinitely pending.

This request has the header "text/event-stream"

When bypassing fortiweb and accessing directly apache in HTTPS (HTTP2), everything is fine.

Could it be that fortiweb (7.6.4) has some issue heandling SSE requests ?

Thank you for your help

Regards

Thibaut

[abelio]

Hello Thibaut

Let assume you're running your fweb in Reverse Proxy. 
If deployment mode is Single Server/Server Balance: did you enable HTTP/2 in the server policy AND in relevant server pool ?

Otherwise, If the Deployment Mode in your server policy conf is
HTTP Content Routing and you enabled HTTP/2 , verify your server pool and disable HTTP/2 (because traffic between fweb and backend server must be HTTP)

These were settings for 7.4x, I guess  that there' re not changes in  7.6.4 for http/2.

Hope it helps

[ajdonik]

Hello Abelio,

Thank you for your reply.

Deployment mode is HTTP Content Routing.

I have tried several combinations :

• Server pool HTTP/2 on and Server policy HTTP/2 on -> impossible to connect (0 byte response)
• Server pool HTTP/2 Off and Server policy HTTP/2 on -> Works fine
• Server pool HTTP/2 On and Server Policy HTTP/2 Off -> applications loads until request with header "text/event-stream" is sent, then pending status on this request in my browser (tested with several browsers also in private mode).
• Server pool HTTP/2 Off and Server policy HTTP/2 off -> Works fine

Here is 2 screenshots from the last (working) configuration :

server policy http2 offserver pool http2 off

So far, i have a workaround (disabling HTTP2), but for better performances it would be better to have it working in HTTP2.

Kind Regards

Thibaut

[abelio · Accepted solution]

Hello Thibaut

If your deploy mode is content routing , you should  disable HTTP/2 in the server pool config
(and enabled in the server policy)

Explanation is: even clients use HTTP/2 , the traffic Fortiweb<->server web must be HTTP; because of that you disable http/2 in the server pool

hope it helps

[ajdonik]

Hello,

Sorry I moved to fast the topic status to "solved".

As soon as i turn HTTP2 on in server policy, the browser keeps pending on "text/event-stream" request.

Whatever the value of HTTP2 in server pool.

Only disabling HTTP2 (between browser and fortiweb) works.

Kind regards

Thibaut

[abelio]

Hello Thibaut

I'm sorry this issue continues;  I´d suggest to open a TAC ticket in order to troubleshoot your specific scenario
No problem with the 'solved'status you made, I guess that it can be removed, or moderator could do that

best regards