Varnish probe thinks web is down if he gets 103 http code

Micu.s Electrobang

1/8/23, 11:24 AM

This is my first post in this forum and I will say that I am sorry for all the mistakes that I will make in this post. This is a desperate call for help as I was not able to find any kind of information on my problem. I am only 20 years old and i just started learning linux 2 years ago. I have a server setup with apache (a very old version), nginx and varnish. The varnish has a health probe for the web and it probes the status of a custom server_status php. it works perfectly fine most of the time but sometimes, the server_status.php will return a 103 status code.

This status code of 103 will trick the probe into thinking the web is sick and for 10-15 seconds, the backend server will return 502. I did some digging and sow that 103 is for early hints and that it comes from apache. I was also able to see that apache will need http2 in order to return 103 codes but as I said, I do not have http2. This apache is too old to know what http2 is.

This is what I get for that probe check:

- - [07/Sep/2021:11:19:38 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"
- - [07/Sep/2021:11:19:38 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"
- - [07/Sep/2021:11:19:40 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"
- - [07/Sep/2021:11:19:41 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"
- - [07/Sep/2021:11:20:06 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"
- - [07/Sep/2021:11:20:06 +0300] "GET /server_status/index.php HTTP/1.1" 103 347 "-" "-"

How can I troubleshoot this and find a solution. I was not able to find anything on google about this problem. If anyone can direct me to the resources that I need in order to find a solution, that will be awesome!!

Thank you very much, Alexandru.

0 + 1

http

nginx

varnish

apache-2.2

apache2

Michael Hampton

1/9/23, 3:05 AM

Change the health check code so that it does not send a 103 response.

Micu.s Electrobang

1/10/23, 7:29 AM

The Server_status code is a verry simple one. It does not send any 103 code. There is something else that does that and I do not know how to figure out what it is.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Varnish probe thinks web is down if he gets 103 http code

TH: โพรบวานิชคิดว่าเว็บหยุดทำงานถ้าเขาได้รับรหัส http 103

RO: Sonda Varnish crede că web este oprită dacă primește codul http 103

RU: Зонд Varnish считает, что сеть не работает, если получает http-код 103

VI: Đầu dò Varnish cho rằng web bị sập nếu anh ta nhận được mã http 103

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