Magento 2 Configured Varnish after check X-Magento-Cache-Debug show Miss?

Question

i have configured varnish in magento 2.4.5. i am getting varnishlog command X-Magento-Cache-Debug: MISS. currently i am using apache server.

I have configure varnish in Magento 2.4.5. Backend configured as per the below Screenshot. https://i.imgur.com/j0Oj2UL.png

but in frontend not show "X-Magento-Cache-Debug:MISS/HIT".

https://i.imgur.com/6QMBU1o.png

i have checked in server log using the below command.i am getting the below response and get

X-Magento-Cache-Debug : MISS

sudo varnishlog

* << Request >> 66232
- Begin req 66231 rxreq
- Timestamp Start: 1685699104.524062 0.000000 0.000000
- Timestamp Req: 1685699104.524062 0.000000 0.000000
- VCL_use boot
- ReqStart 127.0.0.1 51720 a0
- ReqMethod GET
- ReqURL /health_check.php
- ReqProtocol HTTP/1.1
- ReqHeader Host: localhost
- ReqHeader Connection: close
- ReqHeader X-Forwarded-For: 127.0.0.1
- VCL_call RECV
- VCL_return pass
- VCL_call HASH
- VCL_return lookup
- VCL_call PASS
- VCL_return fetch
- Link bereq 66233 pass
- Timestamp Fetch: 1685699104.524305 0.000242 0.000242
- RespProtocol HTTP/1.1
- RespStatus 503
- RespReason Backend fetch failed
- RespHeader Date: 2023年6月02日 09:45:04 GMT
- RespHeader Server: Varnish
- RespHeader content-type: text/html; charset=utf-8
- RespHeader Retry-After: 5
- RespHeader X-Varnish: 66232
- RespHeader Age: 0
- RespHeader Via: 1.1 varnish (Varnish/6.6)
- VCL_call DELIVER
- RespHeader **X-Magento-Cache-Debug: MISS**
- RespHeader Pragma: no-cache
- RespHeader Expires: -1
- RespHeader Cache-Control: no-store, no-cache, must-revalidate, max-age=0
- RespUnset Age: 0
- RespUnset Server: Varnish
- RespUnset X-Varnish: 66232
- RespUnset Via: 1.1 varnish (Varnish/6.6)
- VCL_return deliver
- Timestamp Process: 1685699104.524348 0.000285 0.000043
- Filters
- RespHeader Content-Length: 282
- RespHeader Connection: close
- Timestamp Resp: 1685699104.524431 0.000368 0.000082
- ReqAcct 70 0 70 293 282 575
- End

I have debug it /etc/varnish/default.vcl file and check "sub vcl_deliver". if condition resp.http.x-varnish not true that's why it will not Hit Varnish.

sub vcl_deliver {
 
 if (resp.http.x-varnish ~ " ") {
 set resp.http.X-Magento-Cache-Debug = "HIT";
 set resp.http.Grace = req.http.grace;
 } else {
 set resp.http.X-Magento-Cache-Debug = "MISS";
 }
 # Not letting browser to cache non-static files.
 if (resp.http.Cache-Control !~ "private" && req.url !~ "^/(pub/)?(media|static)/") {
 set resp.http.Pragma = "no-cache";
 set resp.http.Expires = "-1";
 set resp.http.Cache-Control = "no-store, no-cache, must-revalidate, max-age=0";
 }
 if (!resp.http.X-Magento-Debug) {
 unset resp.http.Age;
 }
 unset resp.http.X-Magento-Debug;
 unset resp.http.X-Magento-Tags;
 unset resp.http.X-Powered-By;
 unset resp.http.Server;
 unset resp.http.X-Varnish;
 unset resp.http.Via;
 unset resp.http.Link;
}

we have configured Port on varnish.service file as per the below screenshot.

File Path : /etc/varnish/default.vcl

https://i.imgur.com/SdJ5Yeg.png

File Path : /etc/systemd/system/varnish.service

https://i.imgur.com/kasjhbh.png

i have run server the below command i am getting the below o/p in terminal.

sudo varnishlog -g raw -i backend_health

0 Backend_health - default Still sick -------- 0 5 10 0.000000 0.000000 "Open error 110 (Connection timed out)"
 0 Backend_health - default Still sick -------- 0 5 10 0.000000 0.000000 "Open error 110 (Connection timed out)"
 0 Backend_health - default Still sick -------- 0 5 10 0.000000 0.000000 "Open error 110 (Connection timed out)"
 0 Backend_health - default Still sick -------- 0 5 10 0.000000 0.000000 "Open error 110 (Connection timed out)"
 0 Backend_health - default Still sick -------- 0 5 10 0.000000 0.000000 "Open error 110 (Connection timed out)"

Answer 1

The fact that your health check is the only item in the logs probably means that regular requests aren't being sent to Varnish.

While varnishlog output in general is very useful, your log output didn't contain a lot of debuggable information.

If Varnish is not receiving any of the requests, we should look at how Varnish is configured. I advise you to add your systemd settings for the varnishd.service file, this will show in which IP/port varnishd is listening. It might explain why you're not seeing the logs in varnishlog and why the debug header is missing.

Let's start with that and work our way forward.

Update

The root cause of the problem is as expected: Varnish is not listening on port 80.

Your varnish.service file has varnishd listening in port 8080.

Here's the solution:

• Stop varnishd and reconfigure varnish.service to listen on port 80 by setting -a :80
• Stop your web server and make it listen on port 8080
• Run sudo systemctl daemon-reload to make sure systemd is aware of the configure changes
• Restart varnish by running sudo systemctl restart varnish
• Restart your web server
• Alter your Magento configuration for Varnish and set the backend on port 8080 if that is not the case

• pankaj parmar: I have added varnish.service file and default.vcl file screenshot.please check